o\input texinfo               @c             -*- Texinfo -*-
@finalout
@setfilename dejagnu.info
@c
@c This file documents the GNU Testing Framework ``DejaGnu''
@c
@c Copyright (C) 92, 93, 94, 95, 1996 Free Software Foundation, Inc.
@c
@c This text may be freely distributed under the terms of the GNU
@c General Public License.
@c

@c FIXME---MAIN TODO LIST!
@c
@c * Revisit organization.
@c 
@c * discuss Tcl/expect basics---enough to get started (see seminar notes).
@c   Maybe this would permit abbreviating appendices.

@ifinfo
@format
START-INFO-DIR-ENTRY
* DejaGnu: (dejagnu).            The GNU testing framework.
END-INFO-DIR-ENTRY
@end format
@end ifinfo

@syncodeindex ky cp
@syncodeindex fn cp

@setchapternewpage odd
@settitle DejaGnu Testing Framework
@titlepage
@title The DejaGnu Testing Framework
@subtitle for DejaGnu Version 1.3
@sp 1
@subtitle Jan 1996
@author Rob Savoye
@page

@tex
{\parskip=0pt \hfill Cygnus Support}
@end tex

@vskip 0pt plus 1filll
Copyright @copyright{} 92, 93, 94, 95, 1996 Free Software Foundation, Inc.

Permission is granted to make and distribute verbatim copies of
this manual provided the copyright notice and this permission notice
are preserved on all copies.

@noindent
Permission is granted to copy and distribute modified versions of this
manual under the conditions for verbatim copying, provided also that
the entire resulting derived work is distributed under the terms of a
permission notice identical to this one.

Permission is granted to copy and distribute translations of this manual
into another language, under the above conditions for modified versions.
@end titlepage

@ifinfo
Copyright @copyright{} 92, 93, 94, 95, 1996 Free Software Foundation, Inc.

Permission is granted to make and distribute verbatim copies of
this manual provided the copyright notice and this permission notice
are preserved on all copies.

@ignore
Permission is granted to process this file through TeX and print the
results, provided the printed document carries a copying permission
notice identical to this one except for the removal of this paragraph
(this paragraph not being relevant to the printed manual).
@end ignore

Permission is granted to copy and distribute modified versions of this
manual under the conditions for verbatim copying, provided also that
the entire resulting derived work is distributed under the terms of a
permission notice identical to this one.

Permission is granted to copy and distribute translations of this manual
into another language, under the above conditions for modified versions.

@node Top
@top DejaGnu

DejaGnu is a framework for running test suites on software tools.

This file describes version 1.3 of DejaGnu.

@menu
* Overview::                    What is DejaGnu?
* What is New::                 What is new in this release.
* Invoking runtest::            Using `runtest', the main test driver
* Customizing::			Setting `runtest' defaults
* Internals::                   The DejaGnu implementation
* Tests::                       How to write a test case
* Extending::                   New tools, new targets, and new hosts
* Installation::                Configuring and Installing DejaGnu
* Index::                       Index
@end menu
@end ifinfo

@iftex
@raggedbottom
@end iftex

@node Overview
@chapter What is DejaGnu?
@cindex overview

DejaGnu is a framework for testing other programs.  Its purpose is to
provide a single front end for all tests.  Beyond this, DejaGnu offers
several advantages for testing:

@enumerate
@item
The flexibility and consistency of the DejaGnu framework make it easy
to write tests for any program.

@item
DejaGnu provides a layer of abstraction which allows you to write tests
that are portable to any host or target where a program must be tested.
For instance, a test for GDB can run (from any Unix based host) on any
target architecture that DejaGnu supports. Currently DejaGnu runs tests
on several single board computers, whose operating software ranges from
just a boot monitor to a full-fledged, Unix-like realtime OS.

@item
All tests have the same output format.  This makes it easy to integrate
testing into other software development processes. DejaGnu's output is
designed to be parsed by other filtering script, and it is also human
readable.
@end enumerate

DejaGnu is written in @code{expect}, which in turn uses @dfn{Tcl}---Tool
command language.

@cindex @code{expect} script names
@kindex .exp
@cindex suffix, @code{expect} scripts
Running tests requires two things: the testing framework, and the test
suites themselves.  Tests are usually written in @code{expect} using
Tcl, but you can also use a Tcl script to run a test suite that is not
based on @code{expect}.  (@code{expect} script filenames conventionally
use @samp{.exp} as a suffix; for example, the main implementation of the
DejaGnu test driver is in the file @file{runtest.exp}.)


@menu
* Running Tests::               A first look at running DejaGnu tests
* Sample Test::                 What does a DejaGnu test case look like?
* Design Goals::                Goals behind DejaGnu
* Posix::			DejaGnu conforms to POSIX 1003.3
* Future Directions::           Where is DejaGnu going?
* Tcl and Expect::              Reading more about Tcl and Expect
@end menu

@node What is New
@chapter What is new in this release ?
@cindex What is New

This release has a number of substantial changes over version 1.2. The
most visible change is that the version of expect and Tcl included in
the release are up-to-date with the current stable net releases. Other
changes are:

@enumerate
@item
@c FIXME: add a link to the config section
The config sub-system in DejaGnu has been completely redesigned. It now
supports testing on remote hosts as well as remote targets.

@item
More builtin support for building target binaries with the correct
linker flags. Currently this only works with GCC, preferably with a
target support by @code{libgloss}.

@item
Lots of little bug fixes from a year of heavy use here at Cygnus
Support.

@item
DejaGnu now uses @code{autoconf} for configuration.

@item
New test cases for DejaGnu have been added for the new features, plus
the "--tool" option bug in the 1.2 testsuite has been fixed.

@item
The @code{--tool} option is now optional.

@item
@code{runtest} when searching for test drivers ignores all directories
named SCCS, RCS, and CVS.

@item
There is now a generic keyword based test harness that uses comments in
source code to control how each test case gets built and run.

@item
There is now some support for running a testsuite with multiple passes
and multiple targets.

@end enumerate

@node Running Tests
@section Running existing tests
@cindex existing tests, running
@cindex running tests
@cindex tests, running

@kindex make check
To run tests from an existing collection, first use @code{configure} as
usual to set up the source directory containing the tests.  Then try
running

@example
make check
@end example

@cindex @code{check} makefile target
If the @code{check} target exists, it usually saves you some
trouble---for instance, it can set up any auxiliary programs or other
files needed by the tests.

@cindex auxiliary files, building
Once you have run @samp{make check} to build any auxiliary files, you
might want to call the test driver @code{runtest} directly to repeat the
tests.  You may also have to call @code{runtest} directly for test
collections with no @code{check} target in the @file{Makefile}.

@c force page break to avoid losing footnote to another page
@page
@cindex @code{runtest}, most common options
@cindex options for @code{runtest}, common
Typically, you must use two command-line options: @samp{--tool}, to
specify which set of tests to run@footnote{@samp{--tool} selects a
particular suite of tests, @emph{not} the name of the executable program
to run.  @xref{Config Values,,Configuration dependent values}, for
information on the variables that you can use to specify the names of
programs to run.}, and @samp{--srcdir}, to specify where to find test
directories.

For example, if the directory @file{gdb/testsuite} contains a collection
of DejaGnu tests for @sc{gdb}, you can run them like this:

@example
eg$ cd gdb/testsuite
eg$ runtest --tool gdb
@exdent @emph{Test output follows, ending with:}

		=== gdb Summary ===

# of expected passes 508
# of expected failures 103
/usr/latest/bin/gdb version 4.14.4 -nx
@end example

You can use the option @samp{--srcdir} to point to some other directory
containing a collection of tests:

@smallexample
eg$ runtest --tool gdb --srcdir /devo/gdb/testsuite
@end smallexample

@cindex native configuration
@cindex cross configuration
These examples assume a @dfn{native} configuration, where the same
computer runs both @code{runtest} and the tests themselves.  When you
have a @dfn{cross} configuration, the tests run on a different computer,
controlled by the host running @code{runtest}.  In this situation, you
need the option @samp{--name} to specify the network address for the
other computer:

@smallexample
eg$ runtest --tool gdb --name vx9.munist.com
@end smallexample

If you always use the same option values, you can record them in a file
called @file{site.exp}, rather than typing them each time.  @xref{Config
Values,,Setting defaults for @code{runtest} options}.

By default, @code{runtest} prints only the names of the tests it runs,
output from any tests that have unexpected results, and a summary
showing how many tests passed and how many failed.  To display output
from all tests (whether or not they behave as expected), use the
@samp{--all} option.  For more verbose output about processes being run,
communication, and so on, use @samp{--verbose}. To see even more output,
use multiple @samp{--verbose} options.  @xref{Invoking runtest,,Using
@code{runtest}}, for a more detailed explanation of each @code{runtest}
option.

Test output goes into two files in your current directory: summary
output in @file{@var{tool}.sum}, and detailed output in
@file{@var{tool}.log}.  (@var{tool} refers to the collection of tests;
for example, after a run with @samp{--tool gdb}, look for output files
@file{gdb.sum} and @file{gdb.log}.)  @xref{Output Files,,The files
DejaGnu writes}.

@node Sample Test
@section What does a DejaGnu test look like?

@cindex example
Each DejaGnu test is an @code{expect} script; the tests vary widely in
complexity, depending on the nature of the tool and the feature tested.

@kindex gdb.t00/echo.exp
@kindex echo.exp
Here is a very simple @sc{gdb} test---one of the simplest tests shipped
with DejaGnu (extracted from @file{gdb.t00/echo.exp}):@footnote{More
recent @sc{gdb} tests use the @samp{gdb_test} procedure.
An equivalent test using that procedure is @samp{ gdb_test "echo Hello
world!" "Hello world!" }}
@c FIXME! include xref in footnote, when gdb_test documented in some manual.
@c @xref{}.
@c Extra spaces in @samp above avoid running end ' against " inside.

@cartouche
@smallexample
# send a string to the GDB stdin:
send "echo Hello world!\n"

# inspect the GDB stdout for the correct reply,
# and determine whether the test passes or fails:
expect @{
  -re "Hello world.*$prompt $"    @{ pass "Echo test" @}
  -re "$prompt $"                 @{ fail "Echo test" @}
  timeout                         @{ fail "(timeout) Echo test" @}
  @}
@end smallexample
@end cartouche

Though brief, this example is a complete test.  It illustrates some of
the main features of DejaGnu test scripts:

@itemize @bullet
@item
The test case does not start the tested program (@sc{gdb} in this case);
all test scripts for interactive tools can assume the corresponding tool
is running.

@item
Comments start with @samp{#}.

@item
The main commands you use to control a tested program are @code{send}
(to give it commands) and @code{expect} (to analyze its responses).

@item
The @code{expect} command uses a list of pairs; a pattern (regular
expression if @samp{-re} specified), followed by an action to run if the
pattern matches output from the program.  Only the action for the
@emph{first} matching pattern will execute.

@item
Test cases use the commands @code{pass} and @code{fail} to record the
test outcome.
@end itemize

@node Design Goals
@section Design goals
@cindex design goals

DejaGnu grew out of the internal needs of Cygnus Support.  Cygnus
maintains and enhances a variety of free programs in many different
environments, and we needed a testing tool that:

@itemize @bullet
@item
is useful to developers while fixing bugs;

@item
automates running many tests during a software release process;

@item
is portable among a variety of host computers;

@item
supports cross-development testing;

@item
permits testing interactive programs, like @sc{gdb}; and

@item
permits testing batch oriented programs, like @sc{gcc}.
@end itemize

Some of the requirements proved challenging.  For example, interactive
programs do not lend themselves very well to automated testing.  But all
the requirements are important: for instance, it is imperative to make
sure that @sc{gdb} works as well when cross-debugging as it does in a
native configuration.

Probably the greatest challenge was testing in a cross-development
environment (which can be a real nightmare).  Most cross-development
environments are customized by each developer.  Even when buying
packaged boards from vendors there are many differences.  The
communication interfaces vary from a serial line to ethernet.  DejaGnu
was designed with a modular communication setup, so that each kind of
communication can be added as required, and supported thereafter.  Once
a communication procedure is coded, any test can use it.  Currently
DejaGnu can use @code{rsh}, @code{rlogin}, @code{telnet}, @code{tip},
@code{kermit}, and @code{mondfe} for remote communications.

@cindex name ``DejaGnu''
@cindex DejaGnu, the name
@cindex Menapace, Julia
Julia Menapace first coined the term ``Deja Gnu'' to describe an earlier
testing framework at Cygnus Support.  When we replaced it with the
Expect-based framework, it was like DejaGnu all over again@dots{}

@node Posix
@section A POSIX conforming test framework

@cindex POSIX conformance
@cindex standard conformance: POSIX 1003.3
DejaGnu conforms to the @sc{posix} standard for test frameworks.

@cindex TET
@sc{posix} standard 1003.3 defines what a testing framework needs to
provide, in order to permit the creation of @sc{posix} conformance
test suites. This standard is primarily oriented to running @sc{posix}
conformance tests, but its requirements also support testing of features
not related to @sc{posix} conformance.  @sc{posix} 1003.3 does not
specify a particular testing framework, but at this time there is only
one other @sc{posix} conforming test framework:
@sc{tet}.@footnote{@sc{tet} was created by Unisoft for a consortium
comprised of X/Open, Unix International, and the Open Software
Foundation.}

The @sc{posix} documentation refers to @dfn{assertions}.  An assertion
is a description of behavior.  For example, if a standard says ``The sun
shall shine'', a corresponding assertion might be ``The sun is
shining.''  A test based on this assertion would pass or fail depending
on whether it is daytime or nighttime.  It is important to note that the
standard being tested is never 1003.3; the standard being tested is some
other standard, for which the assertions were written.

As there is no test suite to test @emph{testing frameworks} for
@sc{posix} 1003.3 conformance, verifying conformance to this standard is
done by repeatedly reading the standard and experimenting.  One of the
main things 1003.3 does specify is the set of allowed output messages,
and their definitions.  Four messages are supported for a required
feature of @sc{posix} conforming systems, and a fifth for a conditional
feature. DejaGnu supports the use of all five output messages; in this
sense a test suite that uses exactly these messages can be considered
@sc{posix} conforming.  These definitions specify the output of a test
case:

@ftable @code
@cindex success, POSIX definition
@item PASS
A test has succeeded.  That is, it demonstrated that the assertion is true.

@cindex XFAIL, avoiding for POSIX
@item XFAIL
@sc{posix} 1003.3 does not incorporate the notion of expected failures,
so @code{PASS}, instead of @code{XPASS}, must also be returned for test
cases which were expected to fail and did not.  This means that
@code{PASS} is in some sense more ambiguous than if @code{XPASS} is also
used.  For information on @code{XPASS} and @code{XFAIL}, see
@ref{Invoking runtest,,Using @code{runtest}}.

@item FAIL
@cindex failure, POSIX definition
A test @emph{has} produced the bug it was intended to capture.  That is,
it has demonstrated that the assertion is false.  The @code{FAIL}
message is based on the test case only.  Other messages are used to
indicate a failure of the framework.

As with @code{PASS}, @sc{posix} tests must return @code{FAIL} rather
than @code{XFAIL} even if a failure was expected.

@item UNRESOLVED
@cindex ambiguity, required for POSIX
A test produced indeterminate results.  Usually, this means the test
executed in an unexpected fashion; this outcome requires that a human
being go over results, to determine if the test should have passed or
failed.  This message is also used for any test that requires human
intervention because it is beyond the abilities of the testing
framework.  Any unresolved test should resolved to @code{PASS} or
@code{FAIL} before a test run can be considered finished.

Note that for @sc{posix}, each assertion must produce a test result
code.  If the test isn't actually run, it must produce @code{UNRESOLVED}
rather than just leaving that test out of the output.  This means that
you have to be careful when writing tests, to not carelessly use tcl
statements like @code{return}---if you alter the flow of control of the
tcl code you must insure that every test still produces some result code.

Here are some of the ways a test may wind up @code{UNRESOLVED}:

@itemize @bullet
@item
A test's execution is interrupted.

@item
A test does not produce a clear result. This is usually because there
was an @code{ERROR} from DejaGnu while processing the test, or because there
were three or more @code{WARNING} messages. Any @code{WARNING} or
@code{ERROR} messages can invalidate the output of the test.  This
usually requires a human being to examine the output to
determine what really happened---and to improve the test case.

@item
A test depends on a previous test, which fails.

@item
The test was set up incorrectly.
@end itemize

@item UNTESTED
A test was not run.  This is a placeholder, used when there is no
real test case yet.
@end ftable

@noindent
The only remaining output message left is intended to test features that
are specified by the applicable @sc{posix} standard as conditional:

@ftable @code
@item UNSUPPORTED
There is no support for the tested case.  This may mean that a
conditional feature of an operating system, or of a compiler, is not
implemented.  DejaGnu also uses this message when a testing environment
(often a ``bare board'' target) lacks basic support for compiling or
running the test case.  For example, a test for the system subroutine
@code{gethostname} would never work on a target board running only a
boot monitor.
@end ftable
  
DejaGnu uses the same output procedures to produce these messages for
all test suites, and these procedures are already known to conform to
@sc{posix} 1003.3.  For a DejaGnu test suite to conform to @sc{posix}
1003.3, you must avoid the @code{setup_xfail} procedure as described in
the @code{PASS} section above, and you must be careful to return
@code{UNRESOLVED} where appropriate, as described in the
@code{UNRESOLVED} section above.

@node Future Directions
@section Future directions
@cindex future directions

In the near future, there are two parallel directions for DejaGnu
development.  The first is to add support for more hosts and targets.

The second would permit testing programs with a more complex interface,
whether text based or GUI based.  Two components already exist: a Tcl
based X window toolkit, and a terminal package for @code{expect}. Both
of these could be merged into DejaGnu in a way that permits testing
programs that run in each environment.

Meanwhile, we hope DejaGnu enables the creation of test suites for
conformance to @sc{ansi} C and C++, to @sc{posix}, and to other
standards.  We encourage you to make any test suites you create freely
available, under the same terms as DejaGnu itself.

@node Tcl and Expect
@section Tcl and Expect
@cindex tool command language
@cindex tcl
@cindex Ousterhout, John K.
Tcl was introduced in a paper by John K. Ousterhout at the 1990 Winter
Usenix conference, @cite{Tcl: An Embeddable Command Language}.  That
paper is included in PostScript form in the @file{doc} subdirectory of
the Tcl distribution. The version of Tcl included in DejaGnu at this time is
Tcl 7.4p3. 

@cindex @code{expect} scripting language
@cindex Libes, Don
Don Libes introduced @code{expect} in his paper @cite{expect: Curing
Those Uncontrollable Fits of Interaction} at the 1990 Summer Usenix
conference.  The paper is included in PostScript form in the
@code{expect} distribution (as are several other papers about
@code{expect}). The version of expect included in DejaGnu at this time
is expect 5.18.0.

@node Invoking runtest
@chapter Using @code{runtest}
@cindex invoking
@cindex running
@cindex command line options
@cindex options

@cindex @code{runtest} description
@cindex DejaGnu test driver
@code{runtest} is the executable test driver for DejaGnu.  You can
specify two kinds of things on the @code{runtest} command line: command
line options, and Tcl variables for the test scripts.  The options are
listed alphabetically below.  

@cindex exit code from @code{runtest}
@cindex @code{runtest} exit code
@code{runtest} returns an exit code of @code{1} if any test
has an unexpected result; otherwise (if all tests pass or fail as
expected) it returns @code{0} as the exit code.

@code{runtest} flags the outcome of each test as one of these cases.
(@xref{Posix,,A POSIX conforming test framework}, for a discussion of
how @sc{posix} specifies the meanings of these cases.)

@table @code
@item PASS
@kindex PASS
@cindex successful test
@cindex test, successful
The most desirable outcome: the test succeeded, and was expected to
succeed.

@item XPASS
@kindex XPASS
@cindex successful test, unexpected
@cindex unexpected success
A pleasant kind of failure: a test was expected to fail, but succeeded.
This may indicate progress; inspect the test case to determine whether
you should amend it to stop expecting failure.

@item FAIL
@kindex FAIL
@cindex failing test, unexpected
@cindex test, failing
A test failed, although it was expected to succeed.  This may indicate
regress; inspect the test case and the failing software to locate the bug.

@item XFAIL
@kindex XFAIL
@cindex expected failure
@cindex failing test, expected
A test failed, but it was expected to fail.  This result indicates no
change in a known bug.  If a test fails because the operating system
where the test runs lacks some facility required by the test, the
outcome is @code{UNSUPPORTED} instead.

@item UNRESOLVED
@kindex UNRESOLVED
@cindex test, unresolved outcome
Output from a test requires manual inspection; the test suite could not
automatically determine the outcome.  For example, your tests can report
this outcome is when a test does not complete as expected.

@item UNTESTED
@kindex UNTESTED
@cindex untested properties
A test case is not yet complete, and in particular cannot yet produce a
@code{PASS} or @code{FAIL}.  You can also use this outcome in dummy
``tests'' that note explicitly the absence of a real test case
for a particular property.

@item UNSUPPORTED
@kindex UNSUPPORTED
@cindex unsupported test
@cindex test, unsupported
A test depends on a conditionally available feature that does not exist
(in the configured testing environment).  For example, you can use this
outcome to report on a test case that does not work on a particular
target because its operating system support does not include a required
subroutine.
@end table

@code{runtest} may also display the following messages:

@table @code
@item ERROR
@kindex ERROR
@cindex problem, detected by test case
@cindex test case cannot run
Indicates a major problem (detected by the test case itself) in running
the test. This is usually an unrecoverable error, such as a missing file
or loss of communication to the target.  (@sc{posix} test suites should
not emit this message; use @code{UNSUPPORTED}, @code{UNTESTED}, or
@code{UNRESOLVED} instead, as appropriate.)

@item WARNING
@kindex WARNING
@cindex test case warnings
Indicates a possible problem in running the test. Usually warnings
correspond to recoverable errors, or display an important message about
the following tests.

@item NOTE
@kindex NOTE
@cindex test case messages
An informational message about the test case.
@end table

This is the full set of command line options that @code{runtest}
recognizes.  Arguments may be abbreviated to the shortest unique string.

@cindex @code{runtest} option list
@cindex option list, @code{runtest}
@smallexample
runtest --tool @var{tool}  [ @var{testsuite}.exp @dots{} ]
[ @var{testsuite}.exp="testfile1 @dots{}" ]
[ @var{tclvar}=@var{value}@dots{} ]
[ --all ]  [ --baud @var{baud-rate} ]  [ --connect @var{type} ]
[ --debug ]  [ --help ]  [ --host @var{string} ]
[ --mail "@var{name} @dots{}" ]  [ --name @var{string} ]
[ --name @var{name} ]  [ --outdir @var{path} ]
[ --objdir @var{path} ]  [ --reboot ]
[ --srcdir @var{path} ]  [ --strace @var{n} ]
[ --target @var{string} --build @var{string} ]
[ -v | --verbose ]  [ -V | --version ]  [ --D@var{n} ]
@end smallexample

@table @code
@item --tool @var{tool}
@cindex selecting tests for a tool
@cindex @code{--tool} (@code{runtest} option)
@var{tool} specifies what set of tests to run, and what initialization
module to use.  @var{tool} is used @emph{only} for these two purposes:
it is @emph{not} used to name the executable program to test.
Executable tool names (and paths) are recorded in @file{site.exp}
(@pxref{Config Values,,Configuration dependent values}), and you can
override them by specifying Tcl variables on the command line.

For example, including @samp{--tool gcc} on the @code{runtest} command
line runs tests from all test subdirectories whose names match
@file{gcc.*}, and uses one of the initialization modules named
@file{config/*-gcc.exp}.  To specify the name of the compiler (perhaps
as an alternative path to what @code{runtest} would use by default), use
@samp{GCC=@var{binname}} on the @code{runtest} command line.

@item @var{testsuite}.exp @dots{}
@cindex selecting a range of tests
@cindex tests, running specifically
@cindex naming tests to run
Specify the names of testsuites to run.
By default, @code{runtest} runs all tests for the tool, but you can
restrict it to particular testsuites by giving the names of the @samp{.exp}
@code{expect} scripts that control them.

@var{testsuite}.exp may not include path information; use plain filenames.

@item @var{testfile}.exp="testfile1 @dots{}"
@cindex selecting a range of tests
@cindex tests, running specifically
@cindex naming tests to run
Specify a subset of tests in a suite to run.
For compiler or assembler tests, which often use a single @samp{.exp}
script covering many different source files, this option allows you to
further restrict the tests by listing particular source files to compile.
Some tools even support wildcards here.  The wildcards supported depend
upon the tool, but typically they are @code{?}, @code{*}, and @code{[chars]}.

@item @var{tclvar}=@var{value}
@kindex @var{tclvar}=@var{value}
@cindex Tcl variables, defining for @code{runtest}
@cindex command line Tcl variable definition
@cindex @code{runtest}, variable defns on cmdline
You can define Tcl variables for use by your test scripts in the same
style used with @code{make} for environment variables.  For example,
@samp{runtest GDB=gdb.old} defines a variable called @samp{GDB}; when
your scripts refer to @samp{$GDB} in this run, they use the value
@samp{gdb.old}.

The default Tcl variables used for most tools are defined in the main
DejaGnu @code{Makefile}; their values are captured in the
@file{site.exp} file.  @xref{Config Values,,Configuration dependent
values}.

@item --all
@cindex @code{--all} (@code{runtest} option)
@cindex test output, displaying all
Display all test output.  By default, @code{runtest} shows only the
output of tests that produce unexpected results; that is, tests with
status @samp{FAIL} (unexpected failure), @samp{XPASS} (unexpected
success), or @samp{ERROR} (a severe error in the test case itself).
Specify @samp{--all} to see output for tests with status @samp{PASS}
(success, as expected) @samp{XFAIL} (failure, as expected), or
@samp{WARNING} (minor error in the test case itself).

@item --baud @var{baud-rate}
@itemx -b @var{baud-rate}
@cindex baud rate, specifying
@cindex bps, specifying
@cindex @code{--baud} (@code{runtest} option)
@cindex @code{-b} (@code{runtest} option)
Set the default baud rate to something other than 9600.  (Some serial
interface programs, like @code{tip}, use a separate initialization file
instead of this value.)

@item --connect @var{type}
@cindex connecting to target
@cindex @code{--connect} (@code{runtest} option)
@cindex remote testbed, connecting to
@cindex @code{rlogin}, remote testing via
@cindex @code{telnet}, remote testing via
@cindex @code{rsh}, remote testing via
@cindex @code{tip}, remote testing via
@cindex @code{kermit}, remote testing via
@cindex @code{mondfe}, remote testing via
@cindex remote testing via @code{rlogin}
@cindex remote testing via @code{telnet}
@cindex remote testing via @code{rsh}
@cindex remote testing via @code{tip}
@cindex remote testing via @code{kermit}
@cindex remote testing via @code{mondfe}
Connect to a target testing environment as specified by @var{type}, if
the target is not the computer running @code{runtest}.  For example, use
@samp{--connect} to change the program used to connect to a ``bare
board'' boot monitor.  The choices for @var{type} in the DejaGnu 1.0
distribution are @samp{rlogin}, @samp{telnet}, @samp{rsh}, @samp{tip},
@samp{kermit}, and @samp{mondfe}.

@noindent
The default for this option depends on the configuration (@pxref{Cross
Targets,,Remote targets supported}).  The default is chosen to be the
most convenient communication method available, but often other
alternatives work as well; you may find it useful to try alternative
connect methods if you suspect a communication problem with your testing
target.

@item --debug
@cindex @code{--debug} (@code{runtest} option)
@cindex debug log for test cases
@cindex test cases, debug log
@cindex @code{dbg.log} file
Turns on the @code{expect} internal debugging output.  Debugging output
is displayed as part of the @code{runtest} output, and logged to a file
called @file{dbg.log}.  The extra debugging output does @emph{not}
appear on standard output, unless the verbose level is greater than 2
(for instance, to see debug output immediately, specify @samp{--debug -v
-v}).  The debugging output shows all attempts at matching the test
output of the tool with the scripted patterns describing expected
output.  The output generated with @samp{--strace} also goes into
@file{dbg.log}.

@item --help
@itemx -he
@cindex @code{--help} (@code{runtest} option)
@cindex help with @code{runtest}
@cindex @code{runtest}, listing options
Prints out a short summary of the @code{runtest} options, then exits
(even if you also specify other options).

@item --host @var{string}
@cindex @code{--host} (@code{runtest} option)
@cindex specifying the host config name
@cindex host config name, changing
@var{string} is a full configuration ``triple'' name as used by
@code{configure}.  Use this option to override the default string
recorded by your configuration's choice of host.  This choice does not
change how anything is actually configured unless --build is also
specified; it affects @emph{only} DejaGnu procedures that compare the
host string with particular values.  The procedures @code{ishost},
@code{istarget}, @code{isnative}, and @code{setup_xfail} are affected by
@samp{--host}. In this usage, @code{host} refers to the machine that the
tests are to be run on, which may not be the same as the @code{build}
machine. If @code{--build} is also specified, then @code{--host} refers
to the machine that the tests wil, be run on, not the machine DejaGnu is
run on.

@item --build @var{string}
@cindex @code{--build} (@code{runtest} option)
@cindex specifying the build config name
@cindex build config name, changing
@var{string} is a full configuration ``triple'' name as used by
@code{configure}. This is the type of machine DejaGnu and the tools to
be tested are built on. For a normal cross this is the same as the host,
but for a canadian cross, they are seperate.

@item --name @var{name}
@cindex specifying target name
@cindex target machine name
@cindex @code{--name} (@code{runtest} option)
@var{name} is a name for the particular testing target machine (for
cross testing).  If the testing target has IP network support (for
example, @code{RPC} or @code{NFS}), this is the network name for the
target itself.  (@var{name} is @emph{not the configuration string} you
specify as a target with @code{configure}; the @samp{--name} option
names a particular target, rather than describing a class of targets.)
For targets that connect in other ways, the meaning of the @var{name}
string depends on the connection method.  @xref{Cross Targets,,Remote
targets supported}.

@item --name @var{string}
@cindex remote test machine name
@cindex name for remote test machine
Specify a network name of testing target or its host.  The particular
names that are meaningful with @samp{--name} will depend on your site
configuration, and on the connection protocol: for example, @code{tip}
connections require names from a serial line configuration file (usually
called @file{/etc/remote}), while @code{telnet} connections use IP
hostnames.

@item --objdir @var{path}
@cindex @code{--objdir} (@code{runtest} option)
@cindex object directory
@cindex test programs, auxiliary
@cindex auxiliary test programs
Use @var{path} as the top directory containing any auxiliary compiled
test code. This defaults to @file{.}.  Use this option to locate
pre-compiled test code.  You can normally prepare any auxiliary files
needed with @code{make}.

@item --outdir @var{path}
@cindex output directory
@cindex @code{--outdir} (@code{runtest} option)
@cindex log files, where to write
Write output logs in directory @var{path}.  The default is @samp{.}, the
directory where you start @code{runtest}.  This option affects only the
summary and the detailed log files @file{@var{tool}.sum} and
@file{@var{tool}.log}.  The DejaGnu debug log @file{dbg.log} always
appears (when requested) in the local directory.

@item --reboot
@cindex rebooting remote targets
@cindex @code{--reboot} (@code{runtest} option)
Reboot the target board when @code{runtest} initializes.
Usually, when running tests on a separate target board, it is safer to
reboot the target to be certain of its state.  However, when developing
test scripts, rebooting takes a lot of time.

@item --srcdir @var{path}
@cindex source directory
@cindex @code{--srcdir} (@code{runtest} option)
Use @var{path} as the top directory for test scripts to run.
@code{runtest} looks in this directory for any subdirectory whose name
begins with the toolname (specified with @samp{--tool}).  For instance,
with @samp{--tool gdb}, @code{runtest} uses tests in subdirectories
@file{gdb.*} (with the usual shell-like filename expansion).  If you do
not use @samp{--srcdir}, @code{runtest} looks for test directories under
the current working directory.

@item --strace @var{n}
@cindex @code{--strace} (@code{runtest} option)
@cindex tracing Tcl commands
@cindex @code{expect} internal tracing
Turn on internal tracing for @code{expect}, to @var{n} levels deep. By
adjusting the level, you can control the extent to which your output
expands multi-level Tcl statements.  This allows you to ignore some
levels of @code{case} or @code{if} statements.  Each procedure call or
control structure counts as one ``level''.

The output is recorded in the same file, @file{dbg.log}, used for output
from @samp{--debug}.

@item --target @var{string}
@cindex @code{--target} (@code{runtest} option)
@cindex specifying the target configuration
@cindex target configuration, specifying
Use this option to override the default setting (running native tests).
@var{string} is a full configuration ``triple''
name@footnote{Configuration triples have the form
@samp{@var{cpu}-@var{vendor}-@var{os}}.} as used by @code{configure}.
This option changes the configuration @code{runtest} uses for the
default tool names, and other setup information.  @xref{Using
configure,,Using @code{configure}, configure.info, Cygnus configure},
for details about @code{configure} names.

@item --verbose
@itemx -v
@cindex @code{--verbose} (@code{runtest} option)
@cindex @code{-v} (@code{runtest} option)
@cindex turning on output
@cindex output, additional
Turns on more output.  Repeating this option increases the amount of
output displayed.  Level one (@samp{-v}) is simply test output. Level
two (@samp{-v -v}) shows messages on options, configuration, and process
control.  Verbose messages appear in the detailed (@file{*.log}) log
file, but not in the summary (@file{*.sum}) log file.

@item --version
@itemx -V
@cindex @code{-V} (@code{runtest} option)
@cindex @code{--version} (@code{runtest} option)
@cindex version numbers
Prints out the version numbers of DejaGnu, @code{expect} and Tcl, and
exits without running any tests.

@item -D0
@itemx -D1
@cindex starting the tcl debugger
@cindex tcl debugger
@c FIXME!!! we should say a *lot* more about this debugger
Start the internal Tcl debugger.  The Tcl debugger supports breakpoints,
single stepping, and other common debugging activities.  (See @cite{A
Debugger for Tcl Applications} by Don Libes. @footnote{Distributed in
PostScript form with @code{expect} as the file@*
@file{expect/tcl-debug.ps}.})

If you specify @samp{-D1}, the @code{expect} shell stops at a breakpoint
as soon as DejaGnu invokes it.

If you specify @samp{-D0}, DejaGnu starts as usual, but you can enter
the debugger by sending an interrupt (e.g. by typing @key{C-c}).
@end table

@node Customizing
@chapter Setting @code{runtest} defaults

@kindex site.exp
@cindex variables of DejaGnu, defaults
The site configuration file, @file{site.exp}, captures
configuration-dependent values and propagates them to the DejaGnu test
environment using Tcl variables.  This ties the DejaGnu test scripts
into the @code{configure} and @code{make} programs.

@cindex @file{site.exp}, multiple
@cindex overriding @file{site.exp}
DejaGnu supports more than one @file{site.exp} file.  The multiple
instances of @file{site.exp} are loaded in a fixed order built into
DejaGnu (the more local last). The first file loaded is the optional
@code{~/.dejagnurc}, then the local files, and finally the global file.

@enumerate
@item
There is am optional ``master'' @file{site.exp}, capturing configuration values
that apply to DejaGnu across the board, in each configuration-specific
subdirectory of the DejaGnu library directory.  @code{runtest} loads
these values first. @xref{Installation,,Configuring and Installing
DejaGnu}.  The master @file{site.exp} contains the default values for
all targets and hosts supported by DejaGnu. This master file is
identified by setting the environment variable @code{DEJAGNU} to the
name of the file. This is also refered to as the ``global'' config file.

@item
Any directory containing a configured test suite also has a
@file{site.exp}, capturing configuration values specific to the tool
under test.  Since @code{runtest} loads these values last, the
individual test configuration can either rely on and use, or override,
any of the global values from the ``master'' @file{site.exp}.

You can usually generate or update the testsuite @file{site.exp} by
typing @samp{make site.exp} in the test suite directory, after the test
suite is configured.

@item
You can also have a file in your home directory called
@code{.dejagnurc}. This gets loaded first before the other config
files. Usually this is used for personal stuff, like setting
@code{all_flag} so all the output gets printed, or verbosity levels.
@end enumerate

You can further override the default values in a user-editable section
of any @file{site.exp}, or by setting variables on the @code{runtest}
command line.

@menu
* Config Values::               Variables used in the configuration file.
* Master Config File::          The master configuration file.
* Local Config File::           The local configuration file.
* Personal Config File::        The personal configuration file.
@end menu

@node Config Values, Master Config File, , Customizing
@subsection Config Variables
@cindex configuration dependent defaults
@cindex setting defaults for DejaGnu variables

@c NOTE: default values are given via @code{"fubar"} rather than the
@c    more conventional @samp{fubar} to permit a consistent and clear
@c    notation for the empty string (@code{""}), which will work exactly as
@c    typed.

DejaGnu uses a named array in Tcl to hold all the info for each
machine. In the case of a canadian cross, this means host information as
well as target information. The named array is called
@code{target_info}, and it has two indices. The following fields are
part of the array. 

@table @code
@item name
The name of the target. (mostly for error messages) This
should also be the string used for this target's array.
It should also be the same as the linker script so we
can find them dynamically. This should be the same as the argument used
for @code{push_target@{@}}.

@item ldflags 
This is the linker flags required to produce a fully linked
executable. For @code{libgloss} supported targets this is usually just
the name of the linker script. 

@item config
The target canonical for this target. This is used by some init files to
make sure the target is supported.

@item cflags
The flags required to produce an object file from a source file.

@item connect
This is the connectmode for this target. This is for both IP and
serial connections. Typically this is either @code{telnet},
@code{rlogin}, or @code{rsh}.

@item target
This is the hostname of the target. This is for TCP/IP based connections,
and is also used for version of tip that use /etc/remote. 

@item serial
This is the serial port. This is typically /dev/tty? or com?:.

@item netport
This is the IP port. This is commonly used for telneting to target
boards that are connected to a terminal server. In that case the IP port
specifies the which serial port to use.

@item baud 
This is the baud rate for a serial port connection.

@item x10
This is the parameters for an x10 controller. These are simple devices
that let us power cycle or reset a target board remotely. 

@item fileid
This is the fileid or spawn id of of the connection.

@item prompt
a glob style pattern to recognize the prompt.

@item abbrev
abbreviation for tool init files.

@item ioport
This is the port for I/O on dual port systems. In this configuration,
the main serial port @code{0} is usually used for stdin and stdout,
which the second serial port can be used for debugging.
@end table

The first index into the array is the same value as used in the
@code{name} field. This is usually a short version of the name of the
target board. For an example, here's the settings I use for  my
@code{Motorola's} @code{IDP} board and my @code{Motorola} 6U VME
@code{MVME135-1} board. (both m68k targets)
       
@cartouche
@smallexample
# IDP board
set target_info(idp,name)       "idp"
set target_info(idp,ldflags)    "-Tidp.ld"
set target_info(idp,config)     m68k-unknown-aout
set target_info(idp,cflags)     ""
set target_info(idp,connect)    telnet
set target_info(idp,target)     "s7"
set target_info(idp,serial)     "tstty7"
set target_info(idp,netport)    "wharfrat:1007"
set target_info(idp,baud)       "9600"
# MVME 135 board
set target_info(idp,name)       "mvme"
set target_info(idp,ldflags)    "-Tmvme.ld"
set target_info(idp,config)     m68k-unknown-aout
set target_info(idp,cflags)     ""
set target_info(idp,connect)    telnet
set target_info(idp,target)     "s8"
set target_info(idp,serial)     "tstty8"
set target_info(idp,netport)    "wharfrat:1008"
set target_info(idp,baud)       "9600"
@end smallexample
@end cartouche

DejaGnu can use this information to switch between multiple targets in
one test run. This is done through the use of the @code{push_target}
procedure, which is discussed elsewhere.
@c FIXME: write that section and put an xref here

This array can also hold information for a remote host, which is used
when testing a candain cross. In this case, the only thing different is
the index is just @code{host}. Here's the settings I use to run tests
on my NT machine while running DejaGnu on a Unix machine. (in this case
a Linux box)

@cartouche
@smallexample
set target_info(host,name)      "nt-host"
set target_info(host,config)    "386-unknown-winnt"
set target_info(host,connect)   "telnet"
set target_info(host,target)    "ripple"
@end smallexample
@end cartouche

There is more info on how to use these variables in the sections on the
config files. @xref{Master Config File,,Configuration Files}.

@cindex option defaults
@cindex @code{runtest} option defaults
@cindex variables for option defaults
@cindex defaults, option
In the user editable second section of @file{site.exp}, you can not only
override the configuration variables captured in the first section, but
also specify default values for all the @code{runtest} command line
options.  Save for @samp{--debug}, @samp{--help}, and @samp{--version},
each command line option has an associated Tcl variable.  Use the Tcl
@code{set} command to specify a new default value (as for the
configuration variables).  The following table describes the
correspondence between command line options and variables you can set in
@file{site.exp}.  @xref{Invoking runtest,,Running the Tests}, for
explanations of the command-line options.

@kindex all_flag
@kindex baud
@kindex reboot
@kindex outdir
@kindex objdir
@kindex runtests
@kindex ignoretests
@kindex srcdir
@kindex tracelevel
@kindex targetname
@kindex connectmode
@kindex tool
@kindex target_triplet
@kindex host_triplet
@kindex build_triplet
@kindex verbose

@cindex command line option variables
@cindex Tcl variables for option defaults
@cindex default options, controlling
@cindex options, Tcl variables for defaults

@ifinfo
@display
runtest      Tcl   
option     variable     description
__________ ________     ___________________________________________

--all      all_flag     display all test results if set

--baud     baud         set the default baud rate to something other
                        than 9600.
--connect  connectmode  @samp{rlogin}, @samp{telnet}, @samp{rsh}, 
                        @samp{kermit}, @samp{tip}, or @samp{mondfe}

--outdir   outdir       directory for @file{@var{tool}.sum} and @file{@var{tool}.log}

--objdir   objdir       directory for pre-compiled binaries

--reboot   reboot       reboot the target if set to @code{"1"};
                        do not reboot if set to @code{"0"} (the default)

--srcdir   srcdir       directory of test subdirectories

--strace   tracelevel   a number: Tcl trace depth

--tool     tool         name of tool to test; identifies init, test subdir

--verbose  verbose      verbosity level.  As option, use multiple times;
                        as variable, set a number, 0 or greater
--target   target_triplet The canonical configuration string for the target.
--host     host_triplet The canonical configuration string for the host.
--build    build_triplet The canonical configuration string for the
                        build host.

@end display
@end ifinfo

@tex
\vbox{\halign{\hfil \tt #\quad &\quad\tt #\hfil &\hbox{\vtop{{\raggedright\parindent=0pt\parskip=5pt\hsize=2.75in\rm#\strut\par}}}\hfill\cr
\cr
{\it runtest}&{\it Tcl}\cr
{\it option}&{\it variable}&{\it description}\cr
\noalign{\hrule width\hsize}\cr
--all     &all\_flag    &display all test results if set\cr
--baud    &baud         &set the default baud rate to something other
                        than 9600.\cr
--connect &connectmode &@samp{rlogin}, @samp{telnet}, @samp{rsh},
                        @samp{kermit}, @samp{tip}, or @samp{mondfe}\cr
--mail    &mailing\_list&address list for mailing test output\cr
--name    &targetname  &network name of testing target or its host\cr
--outdir  &outdir      &directory for @file{@var{tool}.sum} and @file{@var{tool}.log}\cr
--objdir  &objdir      &directory for compiled binaries\cr
--reboot  &reboot      &reboot the target if set to @code{"1"};
do not reboot if set to @code{"0"} (the default)\cr
--srcdir  &srcdir      &directory of test subdirectories\cr
--strace  &tracelevel  &a number: Tcl trace depth\cr
--tool    &tool        &name of tool to test; identifies init, test subdir\cr
--verbose &verbose     &verbosity level.  As option, use multiple times;
                        as variable, set a number, 0 or greater\cr
--target  &target\_triplet
        &The canonical configuration string for the target.\cr
--host   &host\_triplet &The canonical configuration string for the host.\cr
--build  &build\_triplet &The canonical configuration string for the
                        build host.\cr
}}
@end tex

@node Master Config File, Local Config File, Config Values, Customizing
@subsection Master Config File
@cindex master @file{site.exp}
@cindex @file{site.exp} for all of DejaGnu
The master config file is where all the target specific config variables
get set for a whole site get set. The idea is that for a centralized
testing lab where people have to share a target between multiple
developers. There are settings for both remote targets and remote hosts. 
Here's an example of a Master Config File (also called the Global config
file) for a @emph{canadian cross}. A canadian cross is when you build
and test a cross compiler on a machine other than the one it's to be
hosted on.

Here we have the config settings for our California office. Note that
all config values are site dependant. Here we have two sets of values
that we use for testing m68k-aout cross compilers. As both of these
target boards has a different debugging protocol, we test on both of
them in sequence.

@cartouche
@smallexample
global CFLAGS
global CXXFLAGS

case "$target_triplet" in @{
    @{ "native" @} @{
        set target_abbrev unix
    @}
    @{ "m68*-unknown-aout" @} @{
        set target_abbrev               "rom68k"
        # IDP target                    # IDP board with rom68k monitor
        set target_info(idp,name)       "idp"
        set target_info(idp,ldflags)    "-Tidp.ld"
        set target_info(idp,config)     m68k-unknown-aout
        set target_info(idp,cflags)     ""
        set target_info(idp,connect)    telnet
        set target_info(idp,target)     "s7"
        set target_info(idp,serial)     "tstty12"
        set target_info(idp,netport)    "truckin:1007"
        set target_info(idp,baud)       "9600"
        # MVME target                   # Motorola MVME 135 with BUG monitor
        set target_info(mvme,name)      "mvme"
        set target_info(mvme,ldflags)   "-Tmvme.ld"
        set target_info(mvme,config)    m68k-unknown-aout
        set target_info(mvme,cflags)    ""
        set target_info(mvme,connect)   telnet
        set target_info(mvme,target)    "s4"
        set target_info(mvme,serial)    "tstty8"
        set target_info(mvme,netport)   "truckin:1004"
        set target_info(mvme,baud)      "9600"
     @}
@}
@end smallexample
@end cartouche

 In this case, we have support for several remote hosts for
our m68k-aout cross compiler. Typically the remote Unix hosts run
DejaGnu locally, but we also use them for debugging the testsuites when
we find problems in running on remote hosts. Expect won't run on NT, so
DejaGnu is run on the local build machine, and it'll connect to the NT
host and run all the tests for this cross compiler on that host.

@smallexample
@cartouche
case "$host_triplet" in @{
    "native" @{
    @}
    "i?86-*-linux*" @{                   # Linux host
        set target_info(host,name)      "linux-host"
        set target_info(host,config)    $host_triplet
        set target_info(host,connect)   rlogin
        set target_info(host,target)    chinadoll
    @}
    "i?86-*-winnt                       # NT host
        set target_info(host,name)      "nt-host"
        set target_info(host,config)    i386-unknown-winnt
        set target_info(host,connect)   telnet
        set target_info(host,target)    ripple
    @}
    "hppa*-hp-hpux*" @{                  # HP-UX host
        set target_info(host,name)      "hpux-host"
        set target_info(host,config)    $host_triplet
        set target_info(host,connect)   rlogin
        set target_info(host,target)    slipknot
        @}
    "sparc-sun-sunos*" @{                # SunOS (sun4)
        set target_info(host,name)      "sunos-host"
        set target_info(host,config)    $host_triplet
        set target_info(host,connect)   rlogin
        set target_info(host,target)    darkstar
    @}
@}
@end cartouche
@end smallexample

@node Local Config File, Personal Config File, Master Config File, Customizing
@subsection Local Config File
@cindex local @file{site.exp}
@cindex @file{site.exp} for each tool
It is usually more convenient to keep these ``manual overrides'' in the
@file{site.exp} local to each test directory, rather than in the
``master'' @file{site.exp} in the DejaGnu library.

All local @file{site.exp} usually files have two sections, separated by
comment text. The first section is the part that is generated by
@code{make}. It is essentially a collection of Tcl variable definitions
based on @file{Makefile} environment variables. Since they are generated
by @code{make}, they contain the values as specified by
@code{configure}.  (You can also customize these values by using the
@samp{--site} option to @code{configure}.)  In particular, this section
contains the @file{Makefile} variables for host and target configuration
data. Do not edit this first section; if you do, your changes are replaced
next time you run @code{make}.

The first section starts with:

@cartouche
@smallexample
## these variables are automatically generated by make ##
# Do not edit here. If you wish to override these values
# add them to the last section
@end smallexample
@end cartouche

In the second section, you can override any default values (locally to
DejaGnu) for all the variables.  The 
second section can also contain your preferred defaults for all the
command line options to @code{runtest}. This allows you to easily
customize @code{runtest} for your preferences in each configured
test-suite tree, so that you need not type options repeatedly on the
command line.  (The second section may also be empty, if you do not wish
to override any defaults.)

The first section ends with this line:

@cartouche
@smallexample
## All variables above are generated by configure. Do Not Edit ##
@end smallexample
@end cartouche

You can make any changes under this line. If you wish to redefine a
variable in the top section, then just put a duplicate value in this
second section. Usually the values defined in this config file are
related to the configuration of the test run. This is the ideal place to
set the variables @code{host_triplet}, @code{build_triplet},
@code{target_triplet}. All other variables are tool dependant. ie for
testing a compiler, the value for @var{CC} might be set to a freshly
built binary, as opposed to one in the user's path.

@node Personal Config File, , Local Config File, Customizing
@subsection Personal Config File
@cindex personal config @file{site.exp}
@cindex @file{site.exp} for each person
The personal config file is used to customize @code{runtest's} behaviour
for each person. It's typically used to set the user prefered setting
for verbosity, and any experimental Tcl procedures. My personal
@file{~/.dejagnurc} file looks like:

@cartouche
@smallexample
set all_flag 1
set RLOGIN /usr/ucb/rlogin
set RSH /usr/ucb/rsh
@end smallexample
@end cartouche

Here I set @code{all_flag} so I see all the test cases that PASS along
with the ones that FAIL. I also set @var{RLOGIN} and @code{RSH} to the
BSD version. I have @code{kerberos} installed, and when I rlogin to a
target board, it usually isn't supported. So I use the non secure
versions of these programs rather than the default that's in my path. 

@node Internals
@chapter The DejaGnu Implementation
@cindex operating principles
@cindex internal details

DejaGnu is entirely written in @code{expect}, which uses Tcl as a
command language.  @code{expect} serves as a very programmable shell;
you can run any program, as with the usual Unix command shells---but
once the program is started, your @code{expect} script has fully
programmable control of its input and output.  This does not just apply
to the programs under test; @code{expect} can also run any auxiliary
program, such as @code{diff} or @code{sh}, with full control over its
input and output.

DejaGnu itself is merely a framework for the set of test suites
distributed separately for each @sc{gnu} tool.  Future releases of
@sc{gnu} tools will include even more tests, developed throughout the
free software community.

@kindex runtest.exp
@code{runtest} is the glue to tie together and manage the test scripts.
The @code{runtest} program is actually a simple Bourne shell script that
locates a copy of the @code{expect} shell and then starts the main Tcl
code, @code{runtest.exp}. @code{runtest.exp} itself has these essential
functions:

@enumerate
@item
Parse the command line options, load the library files, and load the
default configuration files.

@item
Locating the individual test scripts.  @code{runtest.exp} locates the tests
by exploiting a straightforward naming convention based on the string
you specify with the @samp{--tool} option.

@item
Providing an extended test environment, by defining additional Tcl
procedures beyond those already in @code{expect}.

@item
Locating target-dependent functions, to standardize the test environment
across a wide variety of test platforms.
@end enumerate

@menu
* Names::                       Conventions for using tool names
* Init Module::			Initialization module
* DejaGnu Builtins::            DejaGnu provides these Tcl procedures
* Target Dependent::            Procedures supplied by the init module
* Cross Targets::		Remote targets supported
* Input Files::                 The files DejaGnu depends on
* Output Files::                The files DejaGnu produces
@end menu

@node Names
@section Conventions for using tool names

@cindex @code{--tool} and naming conventions
@cindex tool names and naming conventions
@cindex naming conventions
DejaGnu uses @samp{$tool}, the name of the tool under test, to tie
together the testing configuration in a straightforward but flexible
way. If there is only one testsuite for a particular application, then
@samp{$tool} is optional.

@samp{$tool} is @emph{not} used to invoke the tool, since sites that run
multiple configurations of a particular tool often call each
configuration by a different name.  @code{runtest} uses the
configuration-dependent variables captured in @file{site.exp} to
determine how to call each tool.

@cindex directory names and @code{--tool}
@cindex test directories, naming
@code{runtest} uses tool names to find directories containing tests.
@code{runtest} scans the source directory (specified with
@code{--srcdir}) for all directories whose names start with the tool
name. It is a common practice to put a period after the tool part of the
name. For instance, directories that start with
@samp{g++.} contain @sc{g++} tests.  To add a new test, just put it in
any directory (create an entirely new directory, if you wish) whose name
follows this convention.

@cindex @code{exp} filename suffix
@cindex test filename
@cindex filename for test files
A test is any file in an appropriately named subdirectory whose name
ends in @samp{.exp} (the conventional way of naming @code{expect}
scripts).  These simple naming conventions make it as simple as possible
to install new tests: all you must do is put the test in the right
directory.

@cindex order of tests
@cindex tests, running order
@code{runtest} sorts the tests in each subdirectory by name (using the
Tcl @code{lsort} command) and runs them in the resulting order.

@node Init Module
@section Initialization module
@cindex tool initialization
@cindex setting up targets

@c FIXME! should this node be merged with "Target dependent"?

@cindex init file, purpose
@cindex starting interactive tools
@cindex initialization
The initialization module (or ``init file'') has two purposes: to
provide tool and target dependent procedures, and to start up an
interactive tool to the point where it is ready to operate.  The latter
includes establishing communications with the target.  All the tests for
interactive programs assume that the tool is already running and
communicating.  Initialization modules for non-interactive programs may
only need to supply the support functions.

@cindex init file name
@cindex name, initialization module
Each test suite directory must contain (in its @file{config}
subdirectory) a separate initialization module for each target.  The
appropriate init file is can be named several ways. The prefered name is
the @emph{os} part of the canonical configuration name with @code{.exp}
as the suffix. An example would be that for an @code{m68k-coff} system,
the @code{target_os} part would be @code{coff}. The next way is for
system where there are short filenames, or a shortcut is desired to
refer to the OS name for that target. This is uses the value of
@code{$target_abbrev} rather than the @code{target_os}.

The final file looked for is simply @file{default.exp}. If there is only
one operating system to support, then this file can be used. It's main
purpose is to offer some support for new operating systems, or for
unsupported cross targets. The last file looked for is
@file{unknown.exp}. This is usually limited to error handling for
unsupported targets. It's whole contents is typically.

@cartouche
@smallexample
perror "Sorry, there is no support for this target"
exit 1
@end smallexample
@end cartouche

At the beginning of the init file, you must first determine the proper
executable name of the tool to execute, since the actual name of the
tool to be tested my vary from system to system. Here's an example
for the @sc{GNU} C compiler.

@cartouche
@smallexample
global AR
# look for the archiver ar
if ![info exists AR] @{
    set AR [findfile $base_dir/../../binutils/ar $base_dir/../../binutils/ar [tr
ansform ar]]
    verbose "AR defaulting to $AR" 2
@}
@}

global CFLAGS
if ![info exists CFLAGS] then @{
    set CFLAGS ""
@}
@end smallexample
@end cartouche
 
It is always a good idea to first check the variable, and only set it if
it has not yet been defined.  Often the proper value of @code{AR} is set
on the command line that invokes @file{runtest}.

@kindex findfile
The @code{findfile} procedure takes as it's first argument a file name
to look for. The second argument is returned if the file is found, and
the third argument is returned if the file is not found. @code{base_dir}
is set internally by DejaGnu to the top level directory of the object
tree.

@kindex transform
The @code{transform} procedure takes as its argument the native name of
a tool (such as @samp{gcc} for the compiler), and returns the name as
configured for that tool in the current installation.  (For example, a
cross-compiling version of @sc{gnu} CC that generates MIPS code may be
installed with a name like @code{mips-idt-ecoff-gcc}.)

In a test running native, writing the Tcl code for initialization is
usually quite simple.  For cross configurations, however, more elaborate
instructions are usually needed to describe how to talk to a remote
target.

Each initialization module defines up to four procedures with standard
names and purposes.  The names of these procedures begin with
@samp{$tool}, the string that identifies tests for a particular tool:
@code{$tool_start}, @code{$tool_load}, @code{$tool_exit}, and
@code{$tool_version}.  For example, the start procedure for @sc{gdb} is
called @code{gdb_start}.  (Since start procedures are used differently
for batch and interactive tools, however, @code{runtest} itself never
calls the start procedure.  Init files for interactive tools are
expected to end by running the start procedure.)

@cindex utilities, loading from init file
@cindex defaults, setting in init file
The initialization module is also a good place to call @code{load_lib}
to get any collections of utility procedures meant for a family of test
cases, and to set up default values for any additional Tcl variables
needed for a specific set of tests.

@xref{Target Dependent,,Target dependent procedures}, for full
descriptions of these procedures.

@node DejaGnu Builtins
@section DejaGnu procedures
@cindex built in procedures, DejaGnu

DejaGnu provides these Tcl procedures for use in test scripts.
You can also use any standard @code{expect} or Tcl function. These
procedures are stored in libraries, which DejaGnu loads at
runtime. Here's explanation of the library procedures that get loaded at
runtime. All other librarys are optional, and need to be loaded by the
testsuite.

@menu
* framework.exp::               Core Internal Procedures.
* remote.exp::                  Procedures for remote communication.
* utils.exp::                   Utility procedures.
* target.exp::                  Cross target procedures.
* debugger.exp::                Procedures for debugging your Tcl code.
@end menu

@node framework.exp, remote.exp, ,DejaGnu Builtins
@subsection Core Internal Procedures
@cindex Core Internal Procedures

@xref{Posix,,A POSIX conforming test framework}, for more detailed
explanations of the test outcomes (@samp{FAIL}, @samp{PASS},
@samp{UNTESTED}, @samp{UNRESOLVED}, @samp{UNSUPPORTED}).

@ftable @code
@item perror "@var{string} @var{number}"
@cindex test case, ERROR in
@kindex ERROR
Declares a severe error in the testing framework itself.
@code{perror} writes in the log files a message beginning with
@samp{ERROR}, appending the argument @var{string}. If the optional
@var{number} is supplied, then this is used to set the internal count of
errors to that value.

As a side effect, @code{perror} also changes the effect of the next
@code{pass} or @code{fail} command: the test outcome becomes
@samp{UNRESOLVED}, since an automatic @samp{PASS} or @samp{FAIL} cannot
be trusted after a severe error in the test framework.  If the optional
numeric value is @samp{0}, then there are no further side effects to
calling this function, and the following test outcome doesn't become
@samp{UNRESOLVED}. This can be used for errors with no known side
effects.

@item warning "@var{string} @var{number}"
@cindex test case, WARNING in
@kindex WARNING
Declares detection of a minor error in the test case itself.
@code{warning} writes in the log files a message beginning with
@samp{WARNING}, appending the argument @var{string}.  Use @code{warning}
rather than @code{error} for cases (such as communication failure
to be followed by a retry) where the test case can recover from the
error.  If the optional @var{number} is supplied, then this is used to
set the internal count of warnings to that value.

As a side effect, @code{warning_threshold} or more calls to
@code{warning} in a single test case also changes the effect of the next
@code{pass} or @code{fail} command: the test outcome becomes
@samp{UNRESOLVED} since an automatic @samp{PASS} or @samp{FAIL} may not
be trustworthy after many warnings.  If the optional numeric value is
@samp{0}, then there are no further side effects to calling this
function, and the following test outcome doesn't become
@samp{UNRESOLVED}. This can be used for errors with no known side
effects.

@item note "@var{string}"
@cindex test case, informational messages
@kindex NOTE
Appends an informational message to the log file.
@code{note} writes in the log files a message beginning with
@samp{NOTE}, appending the argument @var{string}.  Use @code{note}
sparingly.  @code{verbose} should be used for most such messages,
but in cases where a message is needed in the log file regardless of
the verbosity level use @code{note}.

@item pass "@var{string}"
@cindex test case, declaring success
Declares a test to have passed.  @code{pass} writes in the 
log files a message beginning with @samp{PASS} (or @code{XPASS}, if
failure was expected), appending the argument @var{string}.

@item fail "@var{string}"
@cindex test case, declaring failure
Declares a test to have failed.  @code{fail} writes in the 
log files a message beginning with @samp{FAIL} (or @code{XFAIL}, if
failure was expected), appending the argument @var{string}.

@item unresolved "@var{string}"
@cindex test case, declaring ambiguity
Declares a test to have an unresolved outcome.  @code{unresolved} writes
in the log file a message beginning with @samp{UNRESOLVED}, appending
the argument @var{string}.  This usually means the test did not execute
as expected, and a human being must go over results to determine if it
passed or failed (and to improve the test case).

@item untested "@var{string}"
@cindex test case, declaring no test
Declares a test was not run.  @code{untested} writes in the log file a
message beginning with @samp{UNTESTED}, appending the argument
@var{string}.  For example, you might use this in a dummy test whose
only role is to record that a test does not yet exist for some feature.

@item unsupported "@var{string}"
@cindex test case, declaring no support
Declares that a test case depends on some facility that does not exist
in the testing environment.  @code{unsupported} writes in the log file a
message beginning with @samp{UNSUPPORTED}, appending the argument
@var{string}.

@item get_warning_threshold
@cindex test case, WARNING threshold
Returns the current value of @code{warning_threshold}.
The default value is 3.

@item set_warning_threshold @var{threshold}
@cindex test case, WARNING threshold
Sets the value of @code{warning_threshold}.
A value of @code{0} disables it: calls to @code{warning} will not turn
a @samp{PASS} or @samp{FAIL} into an @samp{UNRESOLVED}.

@item transform "@var{toolname}"
@cindex transform tool name
@cindex installed tool name
@cindex tool name, as installed
@cindex name transformations
Generates a string for the name of a tool as it was configured and
installed, given its native name (as the argument @var{toolname}).
This makes the assumption that all tools are installed using the same
naming conventions: it extrapolates from the invocation name for
@file{runtest}.  For example, if you call @code{runtest} as
@file{m68k-vxworks-runtest}, the result of @w{@samp{ transform "gcc" }}
is @samp{m68k-vxworks-gcc}.

@item ishost "@var{host}"
@cindex host configuration test
Tests for a particular @emph{host} environment.  If the currently
configured host matches the argument string, the result is @code{1};
otherwise the result is @code{0}.  @var{host} must be a full three-part
@code{configure} host name; in particular, you may not use the shorter
nicknames supported by @code{configure} (but you can use wildcard
characters, using shell syntax, to specify sets of names). 

@item istarget "@var{target}"
@cindex target configuration test
Tests for a particular @emph{target} environment.  If the currently
configured target matches the argument string, the result is @code{1};
otherwise the result is @code{0}.  @var{target} must be a full
three-part @code{configure} target name; in particular, you may not use
the shorter nicknames supported by @code{configure} (but you can use
wildcard characters, using shell syntax, to specify sets of names). If it is
passed a @code{NULL} string, then it returns the name of the build
canonical configuration.

@item isbuild "@var{host}"
@cindex build host configuration test
Tests for a particular @emph{build host} environment.  If the currently
configured host matches the argument string, the result is @code{1};
otherwise the result is @code{0}.  @var{host} must be a full three-part
@code{configure} host name; in particular, you may not use the shorter
nicknames supported by @code{configure} (but you can use wildcard
characters, using shell syntax, to specify sets of names). If it is
passed a @code{NULL} string, then it returns the name of the build
canonical configuration.

item is3way "@var{host}"
@cindex canadian cross configuration test
Tests for a canadian cross. This is when the tests will be run on a
remotly hosted cross compiler. If it is a canadian cross, then the
result is @code{1}; otherwise the result is @code{0}.

@item isnative
@cindex native configuration test
Tests whether the current configuration has the same host and target.
When it runs in a @emph{native} configuration this procedure returns a
@code{1}; otherwise it returns a @code{0}.

@item load_lib "@var{library-file}"
@cindex load library file
Loads the file @var{library-file} by searching a fixed path built into
@code{runtest}.  If DejaGnu has been installed, it looks in a path
starting with the installed library directory.  If you are running
DejaGnu directly from a source directory, without first running
@samp{make install}, this path defaults to the current directory.  In
either case, it then looks in the current directory for a directory
called @code{lib}.  If there are duplicate definitions, the last one
loaded takes precedence over the earlier ones.

@item setup_xfail "@var{config}  @r{[}@var{bugid}@r{]}"
@c two spaces above to make it absolutely clear there's whitespace---a
@c crude sort of italic correction!
@cindex test case, expecting failure
@cindex failure, expected
@cindex expected failure
Declares that the test is expected to fail on a particular set of
configurations.  The @var{config} argument must be a list of full
three-part @code{configure} target name; in particular, you may not use
the shorter nicknames supported by @code{configure} (but you can use the
common shell wildcard characters to specify sets of names).  The
@var{bugid} argument is optional, and used only in the logging file
output; use it as a link to a bug-tracking system such as @sc{gnats}
(@pxref{Overview,, Overview, gnats.info, Tracking Bugs With GNATS}).

@cindex @code{XFAIL}, producing
@cindex @code{XPASS}, producing
Once you use @code{setup_xfail}, the @code{fail} and @code{pass}
procedures produce the messages @samp{XFAIL} and @samp{XPASS}
respectively, allowing you to distinguish expected failures (and
unexpected success!) from other test outcomes.

@emph{Warning:} you must clear the expected failure after using
@code{setup_xfail} in a test case.  Any call to @code{pass} or
@code{fail} clears the expected failure implicitly; if the test has some
other outcome, e.g. an error, you can call @code{clear_xfail} to clear
the expected failure explicitly.  Otherwise, the expected-failure
declaration applies to whatever test runs next, leading to surprising
results.

@item clear_xfail @var{config}
@cindex cancelling expected failure
@cindex expected failure, cancelling
Cancel an expected failure (previously declared with @code{setup_xfail})
for a particular set of configurations.  The @var{config} argument is a
list of configuration target names.  It is only necessary to call
@code{clear_xfail} if a test case ends without calling either
@code{pass} or @code{fail}, after calling @code{setup_xfail}.

@item verbose @r{[}-log@r{]} @r{[}-n@r{]} @r{[}--@r{]} "@var{string}" @var{number}
@cindex @code{verbose} builtin function
Test cases can use this function to issue helpful messages depending on
the number of @samp{--verbose} options on the @code{runtest} command
line.  It prints @var{string} if the value of the variable
@code{verbose} is higher than or equal to the optional @var{number}. The
default value for @var{number} is 1.  Use the optional @samp{-log} argument
to cause @var{string} to always be added to the log file, even if it won't
be printed.  Use the optional @samp{-n} argument to print @var{string}
without a trailing newline.  Use the optional @samp{--} argument if
@var{string} begins with "-".

@end ftable

@noindent
@node remote.exp, utils.exp, framework.exp, DejaGnu Builtins
@subsection Remote Communication Procedures

@kindex remote.exp
@kindex lib/remote.exp
@cindex remote connection procedures
@cindex communications procedures
@file{lib/remote.exp} defines these functions, for establishing and
managing communications:

@emph{Procedures to establish a connection:} Each of these procedures
tries to establish the connection up to three times before returning.
Warnings (if retries will continue) or errors (if the attempt is
abandoned) report on communication failures.  The result for any of
these procedures is either @code{-1}, when the connection cannot be
established, or the spawn ID returned by the @code{expect} command
@code{spawn}.

It use the value of the @code{connect} field in the @code{target_info}
array (was @code{connectmode} as the type of connection to make. Current
supported connection types are tip, kermit, telnet, rsh, rlogin, and
netdata. If the @code{--reboot} option was used on the runtest command
line, then the target is rebooted before the connection is made.

@ftable @code

@item remote_open @var{type}
@cindex Opening a remote connection
@emph{Remote Connection Procedure.} This is passed @emph{host} or
@emph{target}. Host or target refers to whether it is a connection to a
remote target, or a remote host. This opens the connection to the
desired target or host using the default values in the configuration
system. It returns that @code{spawn_id} of the process that manages the
connection. This value can be used in @code{expect} or @code{exp_send}
statements, or passed to other procedures that need the connection
process's id. This also sets the @code{fileid} field in the
@code{target_info} array.


@item remote_close @var{shellid}
@cindex Closing a remote connection
@emph{shellid} is value returned by a call to @code{remote_open}. This
closes the connection to the target so resources can be used by
others. This parameter can be left off if the @code{fileid} field in the
@code{target_info} array is set.

@item telnet @var{hostname} @var{port}
@itemx rlogin @var{hostname}
@itemx rsh @var{hostname}
@cindex IP network procedures
@cindex network (IP) procedures
@emph{IP network procedures.} @var{hostname} refers to the IP address or
name (for example, an entry in @file{/etc/hosts}) for this target.  The
procedure names reflect the Unix utility used to establish a
connection. The optional @var{port} is used to specify the IP port
number. The value of the @code{netport} field in the @code{target_info}
array is used. (was @code{$netport}) This value has two parts, the
hostname and the port number, seperated by a @emph{:}. If @code{host} or
@code{target} is used in the @code{hostname} field, than the config
array is used for all information.

@item tip @var{port}
@cindex serial line connection, @code{tip}
@emph{Serial line procedure.} Connect using the Unix utility @code{tip}.
@var{port} must be a name from the @code{tip} configuration file
@file{/etc/remote}.  Often, this is called @samp{hardwire}, or something
like @samp{ttya}. This file holds all the configuration data for
the serial port. The value of the @code{serial} field in the
@code{target_info} array is used. (was @code{$serialport}) If
@code{host} or @code{target} is used in the @code{port} field, than
the config array is used for all information.

@item kermit @var{port} @var{bps}
@cindex serial line connection, @code{kermit}
@emph{Serial line procedure.}  Connect using the program @code{kermit}.
@var{port} is the device name, e.g. @file{/dev/ttyb}.  @var{bps} is
the line speed to use (in bits per second) for the connection. The value
of the @code{serial} field in the @code{target_info} array is used. (was
@code{$serialport}) If @code{host} or @code{target} is used in the
@code{port} field, than the config array is used for all information.

@end ftable

@noindent
@emph{Procedures to manage a connection:}

@ftable @code
@item tip_download @var{spawnid} @var{file}
@cindex download, @code{tip}
@cindex serial download, @code{tip}
Download @file{@var{file}} to the process @var{spawnid} (the value
returned when the connection was established), using the @code{~put}
command under @code{tip}.  Most often used for single board computers
that require downloading programs in @sc{ascii} S-records.  Returns
@code{1} if an error occurs, @code{0} otherwise.

@item exit_remote_shell @var{spawnid}
@cindex terminating remote connection
@cindex remote connection, ending
Exits a remote process started by any of the connection procedures.
@var{spawnid} is the result of the connection procedure that started the
remote process.

@item download @var{file} @r{[} @var{spawnid} @r{]}
@cindex download a file
After you establish a connection to a target, you can download programs
using this command.  @code{download} reads in @var{file} (object code in
S-record format) and writes it to the device controlling this
@var{spawnid}.  (From the point of view of the target, the S-record file
comes in via standard input.)

If you have more than one target active, you can use the optional argument
@var{spawnid} to specify an alternative target (the default is the most
recently established @var{spawnid}.)
@end ftable

@noindent
@node utils.exp, target.exp, remote.exp, DejaGnu Builtins
@subsection Utility Procedures

@kindex utils.exp
@kindex lib/utils.exp
@file{lib/utils.exp} defines these utility procedures:

@ftable @code
@item getdirs @var{dir}
@itemx getdirs @var{dir} @var{pattern}
@cindex directories matching a pattern
@cindex pattern match, directory
Returns a list of all the directories in the single directory @var{dir}
that match @var{pattern}.  If you do not specify @var{pattern},
@code{getdirs} assumes @samp{*}.  You may use the common shell wildcard
characters in @var{pattern}. If no directories match the pattern, then a
@code{NULL} string is returned.

@item find @var{dir} @var{pattern}
@cindex files matching a pattern
@cindex pattern match, filenames
Search for files whose names match @var{pattern} (using shell wildcard
characters for filename expansion).  Search subdirectories recursively,
starting at @var{dir}.  The result is the list of files whose names
match; if no files match, the result is empty.  Filenames in the result
include all intervening subdirectory names. If no files match the
pattern, then a @code{NULL} string is returned.

@item which @var{binary}
@cindex path lookup
Searches the execution path for an executable file @var{binary}, like
the the BSD @code{which} utility.  This procedure uses the shell
environment variable @samp{PATH}. It returns @code{0} if the binary is
not in the path, or if there is no @samp{PATH} environment variable. If
@var{binary} is in the path, it returns the full path to @var{binary}.

@item grep @var{filename} @var{regexp}
@item grep @var{filename} @var{regexp} line
@cindex regular expression, file contents
@cindex searching file contents
Search the file called @var{filename} (a fully specified path) for lines
that contain a match for regular expression @var{regexp}.  The result is
a list of all the lines that match.  If no lines match, the result is an
empty string.  Specify @var{regexp} using the standard regular
expression style used by the Unix utility program @code{grep}.

Use the optional third argument @samp{line} to start lines in the result
with the line number in @var{filename}.  (This argument is simply an
option flag; type it just as shown---@samp{line}.)

@item diff @var{filename} @var{filename}
@cindex finding file differences
@cindex comparing files
Compares the two files and returns a 1 if they match, or a 0 if they
don't. If @code{verbose} is set, then it'll print the differences to the
screen.

@item slay @var{name}
@cindex slaying processes
This look in the process table for @var{name} and send it a unix
@code{SIGINT}, killing the process.

@item absolute @var{path}
@cindex converting relative paths to absolute
This procedure takes the relative @var{path}, and converts it to an
absolute path.

@item psource @var{filename}
@cindex sourcing Tcl files
This sources the file @var{filename}, and traps all errors. It also
ignores all extraneous output. If there was an error it returns a 1,
otherwise it returns a 0.

@item prune @var{list} @var{pattern}
@cindex list, pruning
Remove elements of the Tcl list @var{list}.  Elements are fields
delimited by spaces.  The result is a copy of @var{list}, without any
elements that match @var{pattern}.  You can use the common shell
wildcard characters to specify @var{pattern}.

@item setenv @var{var} @var{val}
@cindex setting environment variables
Sets the variable @var{var} to the value @var{val}.

@item unsetenv @var{var}
@cindex unsetting environment variables
Unsets the environment variable @var{var}

@item getenv @var{var}
@cindex getting environment variables
returns the value of @var{var} in the environment if it exists,
otherwise it returns @code{NULL}.

@item runtest_file_p @var{runtests} @var{testcase}
@cindex selecting a range of tests
@cindex tests, running specifically
Search @var{runtests} for @var{testcase} and return 1 if found, 0 if not.
@var{runtests} is a list of two elements.  The first is the pathname of
the testsuite expect script running.  The second is a copy of what was
on the right side of the @code{=} if @samp{foo.exp="@dots{}"} was specified,
or an empty string if no such argument is present.
This is used by tools like compilers where each testcase is a file.

@item prune_system_crud @var{system} @var{text}
@cindex pruning system output, examining program output
For system @var{system}, delete text the host or target operating system might
issue that will interfere with pattern matching of program output in
@var{text}.  An example is the message that is printed if a shared library
is out of date.

@end ftable

@noindent
@node target.exp, debugger.exp, utils.exp, DejaGnu Builtins
@subsection Cross target procedure

@kindex target.exp
@kindex lib/target.exp
@file{lib/target.exp} defines these utility procedures:

@ftable @code

@item push_target @emph{name}
@cindex set current target
This makes the target named @emph{name} be the current target
connection. The value of @emph{name} is an index into the
@code{target_info} array and is set in the global config file.

@item pop_target
@cindex unset current target
This unsets the current target connection.

@item list_targets
@cindex lists supported targets
This lists all the supported targets for this architecture.

@item push_host @emph{name}
@cindex set current host
This makes the host named @emph{name} be the current remote host
connection. The value of @emph{name} is an index into the
@code{target_info} array and is set in the global config file.

@item pop_host
@cindex unset current host
This unsets the current host connection.

@c @item compile @emph{file}
@cindex compile a file
This invokes the compiler as set by @code{CC} to compile the file
@emph{file}. The default options for many cross compilation targets are
@emph{guessed} by DejaGnu, and these options can be added to by passing
in more parameters as arguments to @code{compile}. Optionally, this will
also use the value of the @code{cflags} field in the target config
array. If the host is not the same as the build machines, then then
compiler is run on the remote host using @code{execute_anywhere}.

@c @item archive @emph{file}
@cindex archive object files
This produces an archive file. Any parameters passed to @code{archive}
are used in addition to the default flags. Optionally, this will
also use the value of the @code{arflags} field in the target config
array. If the host is not the same as the build machines, then then
archiver is run on the remote host using @code{execute_anywhere}.

@c @item ranlib @emph{file}
@cindex ranlib a file
This generates an index for the archive file for systems that aren't
POSIX yet. Any parameters passed to @code{ranlib} are used in for the
flags.

@item execute_anywhere @emph{cmdline}
@cindex executing commands remotely
This executes the @emph{cmdline} on the proper host. This should be used
as a replacement for the Tcl command @code{exec} as this version
utilizes the target config info to execute this command on the build
machine or a remote host. All config information for the remote host
must be setup to have this command work. If this is a canadian cross,
(where we test a cross compiler that runs on a different host then where
DejaGnu is running) then a connection is made to the remote host and
the command is executed there. It returns either @emph{REMOTERROR} (for
an error) or the output produced when the command was executed. This is
used for running the tool to be tested, not a test case.

@end ftable

@node debugger.exp, , target.exp, DejaGnu Builtins
@subsection Debugging Procedures

@kindex debugger.exp
@kindex lib/debugger.exp
@file{lib/debugger.exp} defines these utility procedures:

@ftable @code

@item dumpvars @emph{expr}
@cindex Print global variable values
This takes a csh style regular expression (glob rules) and prints the
values of the global variable names that match.  It is abbreviated as
@code{dv}

@item dumplocals @emph{expr}
@cindex Print local variable value
This takes a csh style regular expression (glob rules) and prints the
values of the local variable names that match. It is abbreviated as
@code{dl}.

@item dumprocs @emph{expr}
@cindex Print procedure bodies
This takes a csh style regular expression (glob rules) and prints the
body of all procs that match. It is abbreviated as @code{dp}

@item dumpwatch @emph{expr}
@cindex Print watchpoints
This takes a csh style regular expression (glob rules) and prints all
the watchpoints. It is abbreviated as @code{dw}.

@c FIXME: finish these when the code is fixed.
@c @item watcharray @emph{element} @emph{type}
@c @cindex Set a watchpoint on an array
@c This sets an watchpoint of the @emph{element-type} on the 
@c @item watchvar v null type
@c @cindex Set a watchpoint on a variable

@item watchunset @emph{var}
@cindex Watch when a variable is unset
This breaks program execution when the variable @emph{var} is unset. It
is abbreviated as @code{wu}.

@item watchwrite @emph{var}
@cindex Watch when a variable is written
This breaks program execution when the variable @emph{var} is
written. It is abbreviated as @code{ww}.

@item watchread @emph{var}
@cindex Watch when a variable is read
This breaks program execution when the variable @emph{var} is read. It
is abbreviated as @code{wr}.

@item watchdel @emph{watch}
@cindex Delete a watchpoint.
This deletes a the watchpoint for @emph{watch}. It is abbreviated as
@code{wd}.

@item print @emph{var}
@cindex Printing variable values
This prints the value of the variable @emph{var}. It is abbreviated as
@code{p}.

@item quit
@cindex Quiting DejaGnu
This makes runtest exit. It is abbreviated as @code{q}.

@item bt
@cindex Print a backtrace
This prints a backtrace of the executed Tcl commands.

@end ftable

@node Target Dependent
@section Target dependent procedures
@cindex target dependent procedures

@c FIXME? These may be renamed to just "start", "load", "exit", and
@c "version" eventually.

Each combination of target and tool requires some target-dependent
procedures.  The names of these procedures have a common form: the tool
name, followed by an underbar @samp{_}, and finally a suffix describing
the procedure's purpose.  For example, a procedure to extract the
version from @sc{gdb} is called @samp{gdb_version}.  @xref{Init Module,,
Initialization Module}, for a discussion of how DejaGnu arranges to find
the right procedures for each target.

@code{runtest} itself calls only two of these procedures,
@code{@var{tool}_exit} and @code{@var{tool}_version}; these procedures use
no arguments.

The other two procedures, @code{@var{tool}_start} and
@code{@var{tool}_load}, are only called by the test suites themselves
(or by testsuite-specific initialization code); they may take arguments
or not, depending on the conventions used within each test suite.

@ftable @code
@item @var{tool}_start
@cindex start procedure, tested tools
Starts a particular tool.  For an interactive tool,
@code{@var{tool}_start} starts and initializes the tool, leaving the
tool up and running for the test cases; an example is @code{gdb_start},
the start function for @sc{gdb}.  For a batch oriented tool,
@code{@var{tool}_start} is optional; the recommended convention is to
let @code{@var{tool}_start} run the tool, leaving the output in a
variable called @code{comp_output}.  Test scripts can then analyze
@samp{$comp_output} to determine the test results.  An example of this
second kind of start function is @code{gcc_start}, the start function
for @sc{gcc}.

@code{runtest} itself @emph{does not call} @code{@var{tool}_start}.  The
initialization module @file{@var{tool}_init.exp} must call
@code{@var{tool}_start} for interactive tools; for batch-oriented tools,
each individual test script calls @code{@var{tool}_start} (or makes
other arrangements to run the tool).

@item @var{tool}_load
@cindex load procedure, tested tools
Loads something into a tool. For an interactive tool, this conditions
the tool for a particular test case; for example, @code{gdb_load} loads
a new executable file into the debugger. For batch oriented tools,
@code{@var{tool}_load} may do nothing---though, for example, the
@sc{gcc} support uses @code{gcc_load} to load and run a binary on the
target environment.  Conventionally, @code{@var{tool}_load} leaves the
output of any program it runs in a variable called @samp{exec_output}.
Writing @code{@var{tool}_load} can be the most complex part of extending
DejaGnu to a new tool or a new target, if it requires much communication
coding or file downloading.

Test scripts call @code{@var{tool}_load}.

@item @var{tool}_exit
@cindex exit procedure, tested tools
Cleans up (if necessary) before @code{runtest} exits. For interactive
tools, this usually ends the interactive session.  You can also use
@code{@var{tool}_exit} to remove any temporary files left over from the
tests.

@code{runtest} calls @code{@var{tool}_exit}.

@item @var{tool}_version
@cindex version procedure, tested tools
Prints the version label and number for @var{tool}.  This is called by
the DejaGnu procedure that prints the final summary report.  The output
should consist of the full path name used for the tested tool, and its
version number.

@code{runtest} calls @code{@var{tool}_version}.
@end ftable

The usual convention for return codes from any of these procedures
(although it is not required by @code{runtest}) is to return @code{0} if
the procedure succeeded, @code{1} if it failed, and @code{-1} if there
was a communication error.

@node Cross Targets
@section Remote targets supported

@cindex targets
@cindex remote testing
The DejaGnu distribution includes support for the following remote
targets.  You can set the target name and the connect mode in the
@file{site.exp} file (using the Tcl variables @samp{targetname} and
@samp{connectmode}, respectively), or on the @code{runtest} command line
(using @samp{--name} and @samp{--connect}).

@table @strong
@item @sc{amd} 29000, with UDI protocol
Configure DejaGnu for target @samp{a29k-amd-udi}.  (Cygnus
@code{configure} also recognizes the abbreviation @samp{udi29k}.)  Then,
to run tests, use the @code{runtest} target name to specify whether you
want to use a simulator, or a particular hardware board.  The particular
string to use with @samp{--name} will depend on your UDI setup file,
@file{udi_soc} (if @file{udi_soc} is not in your working directory, the
environment variable @samp{UDICONF} should contain a path to this file).
For example, if your UDI setup file includes these lines:
@end table
@c table "ends" *only* to allow wider example below

@cartouche
@smallexample
iss   AF_UNIX  *   isstip -r /home/gnu/29k/src/osboot/sim/osboot
mon   AF_UNIX  *   montip -t serial -baud 9600 -com /dev/ttyb
@end smallexample
@end cartouche

@table @strong
@item @w{ }
@c fake out table/item into continuing w/same margin as before
You can use @samp{--name iss} to run tests on the simulator, and
@samp{--name mon} to run tests on the 29K hardware.  See the
manufacturer's manuals for more information on UDI and @file{udi_soc}.
@c FIXME! Is there a better ref than "the manufacturer's manuals"?

@kindex mondfe
The default connect protocol is @samp{mondfe} with either back end.
@code{mondfe} is the only shell DejaGnu supports for UDI targets.
@code{mondfe} is an @sc{amd} specific monitor program freely available
from @sc{amd}.

@emph{Warning:} This target requires @sc{gdb} version 4.7.2 (or
greater).  Earlier versions of @sc{gdb} do not fully support the
@code{load} command on this target, so DejaGnu has no way to load
executable files from the debugger.

@item Motorola 680x0 boards, a.out or @sc{coff} object format
Configure DejaGnu for any remote target matching @samp{m68k-*}.

@emph{Warning:} Most @samp{m68k-*} configurations run all tests only for
native testing (when the target is the same as the host).  When you
specify most of these targets for a cross configuration, you will only be
able to use tests that run completely within the host (for example,
tests of the binary utilities such as the archiver; or compiler tests
that only generate code rather than running it).

To run a.out or @sc{coff} binaries on a remote M68K, you must configure
DejaGnu for a particular target board.  @samp{m68k-abug} is an example.
(In general for an embedded environment, because it does not have absolute
addresses, a.out is not a good choice for output format in any case; most
often S-records or Hex-32 are used instead.)

@item Motorola 68K MVME 135 board running ABug boot monitor
Configure for @samp{m68k-abug-aout} or @samp{m68k-abug-coff} (as a
target).  This boot monitor can only download S-records; therefore, the
DejaGnu tests for this environment require a linker command script to
convert either output format to S-records, setting the default addresses
for @code{.text}, @code{.bss}, and @code{.data}.

With this configuration, the default for @samp{--connect} is @samp{tip}.
@samp{tip} is the only communications protocol supported for connecting
to @samp{m68k-abug-*} targets.  @samp{tip} uses an @sc{ascii} downloader
(the @code{~put} command) to load S-records into the target board.  The
@samp{--name} string must be a machine name that @code{tip}
understands (for example, on some @code{tip} implementations it must be
an entry from the initialization file for @code{tip}; this file is
sometimes called @file{/etc/remote}).

See your system documentation for information on how to create new
entries in @file{/etc/remote}.  (Some @sc{unix} systems are distributed
with at least one default entry with a name resembling @samp{hardwire};
if your system has one, you can edit it, or make a modified copy with a
new name.)  When you have a working @file{/etc/remote} entry
@var{abugtarget}, you should be able to type @samp{tip
@var{abugtarget}}, and get the prompt @samp{135ABUG>} from the board.
Use the same @var{abugtarget} string with @samp{runtest --name}.

@item Motorola IDP board running the rom68k boot monitor
@c FIXME 1: this doesn't really say anything!  OK, so functionality is
@c the same.  Is object code the same (srecords)?  Do we configure with
@c the same triplets?  What is the default for --connect?  Is
@c any comms method other than tip supported?  What prompt to expect
@c when tip connected?
@c FIXME 2: should @code{BUG} below be @code{ABUG}?
This is the same in functionality as the MVME board running the
@code{BUG} boot monitor. Only the monitor commands and the addresses are
different.

@item VxWorks (Motorola 68K or Intel 960)
Configure DejaGnu for either @samp{m68k-wrs-vxworks} (abbreviated
@samp{vxworks68}) or @samp{i960-wrs-vxworks} (abbreviated
@samp{vxworks960}).  Since both targets support IP addressing, specify
the network address (for example, a host name from @file{/etc/hosts})
with @samp{--name}.

The default connect protocol is @samp{rlogin}, but you can use any of
@samp{--connect rlogin}, @samp{--connect telnet}, or @samp{--connect
rsh}.

Test scripts need no special code to load programs into these targets;
since VxWorks supports NFS, all you must do is ensure test programs are
on an exported filesystem.

@cindex VxWorks, link with @samp{-r}
When you compile for VxWorks, use the linker @samp{-r} option to make
the linker output relocatable---at least if you want to use library
routines. Many standard C routines are included in VxWorks; often no
additional libraries are needed.  See your VxWorks system documentation
for additional details.
@end table

@node Input Files
@section The files DejaGnu reads
@cindex input files

The @code{runtest} program used to invoke DejaGnu is a short shell
script generated by @code{make} during the configuration process.  Its
main task is to read the main test framework driver, @file{runtest.exp}.

@file{runtest.exp}, in turn, reads @code{expect} code from certain other
files, in this order:

@enumerate
@item
Each of the @file{site.exp} local definition files available.
@xref{Customizing,,Setting @code{runtest} defaults}, for details.

@item
@file{lib/utils.exp}, a collection of utility procedures.  @xref{DejaGnu
Builtins,,DejaGnu Builtins}, for descriptions of these procedures.

@item
@file{lib/framework.exp}, a file of subroutines meant for @code{runtest}
itself rather than for general-purpose use in both @code{runtest} and
test suites.

@item
@file{debugger.exp}, Don Libes' Tcl Debugger.  (See @cite{A Debugger for
Tcl Applications} by Don Libes. This paper is distributed with
@code{expect} in PostScript form as the file
@file{expect/tcl-debug.ps}.)

@item
@file{lib/remote.exp}, a collection of subroutines meant for connecting
to remote machines.

@item
@file{lib/target.exp}, a collection of subroutines used for the
configuration systems in DejaGnu. These procedures typically manipulate
or utilize the configuration system.

@item
@c FIXME!  A comment in runtest.exp claims a system default is used if
@c         no tool-specific init file is not available; I couldn't see where
@c         the program flow actually does this, though---pesch 30jul1993.
An initialization file @code{@var{tool}_init.exp}.  @xref{Init
Module,,Initialization module}, for more discussion of init files.
@end enumerate

@c This hard page break is mainly intended for smallbook formatting;
@c some examples in this section come out better if this starts at a
@c page boundary.
@page
@node Output Files
@section The files DejaGnu writes
@cindex output files

@code{runtest} always writes two kinds of output files: summary logs and
detailed logs.  The contents of both of these are determined by your
tests.

For troubleshooting, a third kind of output file is useful: use
@samp{--debug} to request an output file showing details of what
@code{expect} is doing internally.

@menu
* Summary::             Files that summarize tests
* Detail::              Files that contain complete test results
* Debug::               Logging expect internal actions
@end menu

@node Summary
@subsection Summary log
@cindex summary log

@code{runtest} always produces a summary output file
@file{@var{tool}.sum}.  This summary shows the names of all test files
run; for each test file, one line of output from each @code{pass}
command (showing status @samp{PASS} or @samp{XPASS}) or @code{fail}
command (status @samp{FAIL} or @samp{XFAIL}); trailing summary
statistics that count passing and failing tests (expected and
unexpected); and the full pathname and version number of the tool
tested.  (All possible outcomes, and all errors, are always reflected in
the summary output file, regardless of whether or not you specify
@samp{--all}.)

If any of your tests use the procedures @code{unresolved},
@code{unsupported}, or @code{untested}, the summary output also
tabulates the corresponding outcomes.

For example, after @samp{runtest --tool binutils}, look for a summary
log in @file{binutils.sum}.  Normally, @code{runtest} writes this file
in your current working directory; use the @samp{--outdir} option to
select a different directory.

@need 3500
@noindent
Here is a short sample summary log:

@cartouche
@smallexample
Test Run By rob on Mon May 25 21:40:57 PDT 1992
                === gdb tests ===
Running ./gdb.t00/echo.exp ...
PASS:   Echo test
Running ./gdb.all/help.exp ...
PASS:   help add-symbol-file
PASS:   help aliases
PASS:   help breakpoint "bre" abbreviation
FAIL:   help run "r" abbreviation
Running ./gdb.t10/crossload.exp ...
PASS:   m68k-elf (elf-big) explicit format; loaded
XFAIL:  mips-ecoff (ecoff-bigmips) "ptype v_signed_char" signed
C types 
                === gdb Summary ===
# of expected passes 5
# of expected failures 1
# of unexpected failures 1
/usr/latest/bin/gdb version 4.6.5 -q
@end smallexample
@end cartouche

@node Detail
@subsection Detailed log
@cindex detailed log

@code{runtest} also saves a detailed log file @file{@var{tool}.log},
showing any output generated by tests as well as the summary output.
For example, after @samp{runtest --tool binutils}, look for a detailed
log in @file{binutils.log}.  Normally, @code{runtest} writes this file
in your current working directory; use the @samp{--outdir} option to
select a different directory.

@need 4000
@noindent
Here is a brief example showing a detailed log for @sc{g++} tests:

@cartouche
@smallexample
Test Run By rob on Mon May 25 21:40:43 PDT 1992

                === g++ tests ===

--- Running ./g++.other/t01-1.exp ---
        PASS:   operate delete

--- Running ./g++.other/t01-2.exp ---
        FAIL:   i960 bug EOF
p0000646.C: In function `int  warn_return_1 ()':
p0000646.C:109: warning: control reaches end of non-void function
p0000646.C: In function `int  warn_return_arg (int)':
p0000646.C:117: warning: control reaches end of non-void function
p0000646.C: In function `int  warn_return_sum (int, int)':
p0000646.C:125: warning: control reaches end of non-void function
p0000646.C: In function `struct foo warn_return_foo ()':
p0000646.C:132: warning: control reaches end of non-void function

--- Running ./g++.other/t01-4.exp ---
        FAIL:   abort
900403_04.C:8: zero width for bit-field `foo'
--- Running ./g++.other/t01-3.exp ---
        FAIL:   segment violation
900519_12.C:9: parse error before `;'
900519_12.C:12: Segmentation violation
/usr/latest/bin/gcc: Internal compiler error: program cc1plus got
fatal signal

                === g++ Summary ===

# of expected passes 1
# of expected failures 3
/usr/ps/bin/g++ version cygnus-2.0.1
@end smallexample
@end cartouche

@node Debug
@subsection Logging @code{expect} internal actions
@cindex debug log

With the @samp{--debug} option, you can request a log file showing the
output from @code{expect} itself, running in debugging mode. This file
(@file{dbg.log}, in the directory where you start @code{runtest}) shows
each pattern @code{expect} considers in analyzing test output.

This file reflects each @code{send} command, showing the string sent as
input to the tool under test; and each @code{expect} command, showing
each pattern it compares with the tool output.

The log messages for @code{expect} begin with a message of the form

@smallexample
expect: does @{@var{tool output}@} (spawn_id @var{n}) match pattern
@{@var{expected pattern}@}?
@end smallexample

@noindent
For every unsuccessful match, @code{expect} issues a @samp{no} after
this message; if other patterns are specified for the same
@code{expect} command, they are reflected also, but without the first
part of the message (@samp{expect@dots{}match pattern}).  

When @code{expect} finds a match, the log for the successful match ends
with @samp{yes}, followed by a record of the @code{expect} variables set
to describe a successful match.  Here is an excerpt from the debugging
log for a @sc{gdb} test:

@c FIXME! Why is the second spawn_id shown 0 rather than 6?
@cartouche
@smallexample
send: sent @{break gdbme.c:34\n@} to spawn id 6
expect: does @{@} (spawn_id 6) match pattern @{Breakpoint.*at.* file
 gdbme.c, line 34.*\(gdb\) $@}? no
@{.*\(gdb\) $@}? no
expect: does @{@} (spawn_id 0) match pattern @{<return>@}? no
@{\(y or n\) @}? no
@{buffer_full@}? no
@{virtual@}? no
@{memory@}? no
@{exhausted@}? no
@{Undefined@}? no
@{command@}? no
break gdbme.c:34
Breakpoint 8 at 0x23d8: file gdbme.c, line 34.
(gdb) expect: does @{break gdbme.c:34\r\nBreakpoint 8 at 0x23d8: 
file gdbme.c, line 34.\r\n(gdb) @} (spawn_id 6) match pattern
@{Breakpoint.*at.* file gdbme.c, line 34.*\(gdb\) $@}? yes
expect: set expect_out(0,start) @{18@}
expect: set expect_out(0,end) @{71@}
expect: set expect_out(0,string) @{Breakpoint 8 at 0x23d8: file
gdbme.c, line 34.\r\n(gdb) @}
expect: set expect_out(spawn_id) @{6@}
expect: set expect_out(buffer) @{break gdbme.c:34\r\nBreakpoint 8
at 0x23d8: file gdbme.c, line 34.\r\n(gdb) @}
        PASS:   70      0       breakpoint line number in file
@end smallexample
@end cartouche

@noindent
This example exhibits three properties of @code{expect} and DejaGnu that
might be surprising at first glance:

@itemize @bullet
@item
Empty output for the first attempted match.  The first set of attempted
matches shown ran against the output @samp{@{@}}---that is, no output.
@code{expect} begins attempting to match the patterns supplied
immediately; often, the first pass is against incomplete output (or
completely before all output, as in this case).

@item
Interspersed tool output.  The beginning of the log entry for the second
attempted match may be hard to spot: this is because the prompt
@samp{(gdb) } appears on the same line, just before the @samp{expect:}
that marks the beginning of the log entry.  

@item
Fail-safe patterns.  Many of the patterns tested are fail-safe patterns
provided by @sc{gdb} testing utilities, to reduce possible
indeterminacy.  It is useful to anticipate potential variations
caused by extreme system conditions (@sc{gdb} might issue the message
@samp{virtual memory exhausted} in rare circumstances), or by changes in
the tested program (@samp{Undefined command} is the likeliest outcome if
the name of a tested command changes).

The pattern @samp{@{<return>@}} is a particularly interesting fail-safe
to notice; it checks for an unexpected @key{RET} prompt.  This may
happen, for example, if the tested tool can filter output through a
pager.

These fail-safe patterns (like the debugging log itself) are primarily
useful while developing test scripts.  Use the @code{error} procedure to
make the actions for fail-safe patterns produce messages starting with
@samp{ERROR} on the @code{runtest} standard output, and in the detailed
log file.
@end itemize

@node Tests
@chapter How To Write a Test Case
@cindex writing a test case
@cindex test case, writing

@menu
* Writing::                     Writing a test case
* Debugging::                   Debugging a test case
* Adding::                      Adding a test case to a test suite
* Hints::                       Hints on writing a test case
* Variables::                   Special variables used by test cases
@end menu

@node Writing
@section Writing a test case

The easiest way to prepare a new test case is to base it on an existing
one for a similar situation.  There are two major categories of tests:
batch or interactive.  Batch oriented tests are usually easier to write.

The @sc{gcc} tests are a good example of batch oriented tests.  All
@sc{gcc} tests consist primarily of a call to a single common procedure,
since all the tests either have no output, or only have a few warning
messages when successfully compiled.  Any non-warning output is a test
failure.  All the C code needed is kept in the test directory.  The test
driver, written in @code{expect}, need only get a listing of all the C
files in the directory, and compile them all using a generic procedure.
This procedure and a few others supporting for these tests are kept in
the library module @file{lib/c-torture.exp} in the @sc{gcc} test suite.
Most tests of this kind use very few @code{expect} features, and are
coded almost purely in Tcl.

@noindent
Writing the complete suite of C tests, then, consisted of these steps:

@enumerate
@item 
@cindex Granlund, Torbjorn
@cindex C torture test
Copying all the C code into the test directory.  These tests were based on
the C-torture test created by Torbjorn Granlund (on behalf of the Free
Software Foundation) for @sc{gcc} development.

@item
Writing (and debugging) the generic @code{expect} procedures for
compilation.

@item
Writing the simple test driver: its main task is to search the directory
(using the Tcl procedure @code{glob} for filename expansion with
wildcards) and call a Tcl procedure with each filename.  It also checks
for a few errors from the testing procedure.
@end enumerate

Testing interactive programs is intrinsically more complex.  Tests for most
interactive programs require some trial and error before they are complete.

However, some interactive programs can be tested in a simple fashion
reminiscent of batch tests.  For example, prior to the creation of
DejaGnu, the @sc{gdb} distribution already included a wide-ranging
testing procedure.  This procedure was very robust, and had already
undergone much more debugging and error checking than many recent
DejaGnu test cases.  Accordingly, the best approach was simply to
encapsulate the existing @sc{gdb} tests, for reporting purposes.
Thereafter, new @sc{gdb} tests built up a family of @code{expect}
procedures specialized for @sc{gdb} testing.

@file{gdb.t10/crossload.exp} is a good example of an interactive test.
@c FIXME!  Check what *kind* of example it is---work-intensive, or generic...

@node Debugging
@section Debugging a test case
@cindex debugging a test case
@cindex test case, debugging

@noindent
These are the kinds of debugging information available from DejaGnu:

@enumerate
@item
Output controlled by test scripts themselves, explicitly allowed for by
the test author.  This kind of debugging output appears in the detailed
output recorded in the @file{@var{tool}.log} file.  To do the same for
new tests, use the @code{verbose} procedure (which in turn uses the
variable also called @code{verbose}) to control how much output to
generate.  This will make it easier for other people running the test to
debug it if necessary.  Whenever possible, if @samp{$verbose} is
@code{0}, there should be no output other than the output from
@code{pass}, @code{fail}, @code{error}, and @code{warning}.  Then, to
whatever extent is appropriate for the particular test, allow
successively higher values of @samp{$verbose} to generate more
information.  Be kind to other programmers who use your tests: provide
for a lot of debugging information.

@item
Output from the internal debugging functions of Tcl and @code{expect}.
There is a command line options for each; both forms of debugging output
are recorded in the file @code{dbg.log} in the current directory.

Use @samp{--debug} for information from the @code{expect} level; it
generates displays of the @code{expect} attempts to match the tool
output with the patterns specified (@pxref{Debug,,Debug Log}).  This
output can be very helpful while developing test scripts, since it shows
precisely the characters received.  Iterating between the latest attempt
at a new test script and the corresponding @file{dbg.log} can allow you
to create the final patterns by ``cut and paste''.  This is sometimes
the best way to write a test case.

Use @samp{--strace} to see more detail at the Tcl level; this shows how Tcl
procedure definitions expand, as they execute.  The associated number
controls the depth of definitions expanded; see the discussion of
@samp{--strace} in @ref{Invoking runtest,,Running the Tests}.

@item
Finally, if the value of @samp{verbose} is 3 or greater, @code{runtest}
turns on the @code{expect} command @code{log_user}.  This command prints
all @code{expect} actions to the @code{expect} standard output, to the
detailed log file, and (if @samp{--debug} is on) to @file{dbg.log}.
@end enumerate

@node Adding
@section Adding a test case to a test suite
@cindex adding a test case

There are two slightly different ways to add a test case. One is to add
the test case to an existing directory. The other is to create a new
directory to hold your test. The existing test directories represent
several styles of testing, all of which are slightly different; examine
the directories for the tool of interest to see which (if any) is most
suitable.

Adding a @sc{gcc} test can be very simple: just add the C code to any
directory beginning with @samp{gcc.} and it runs on the next
@samp{runtest --tool gcc}.

To add a test to @sc{gdb}, first add any source code you will need to
the test directory. Then you can either create a new @code{expect} file,
or add your test to an existing one (any file with a @samp{.exp}
suffix).  Creating a new @samp{.exp} file is probably a better idea if
the test is significantly different from existing tests. Adding it as a
separate file also makes upgrading easier. If the C code has to be
already compiled before the test will run, then you'll have to add it to
the @file{Makefile.in} file for that test directory, then run
@code{configure} and @code{make}.

Adding a test by creating a new directory is very similar:

@enumerate
@item
Create the new directory. All subdirectory names begin with the name of
the tool to test; e.g. @sc{g++} tests might be in a directory called
@file{g++.other}. There can be multiple test directories that start with
the same tool name (such as @samp{g++}).

@item
Add the new directory name to the @samp{configdirs} definition in the
@file{configure.in} file for the test suite directory. This way when
@code{make} and @code{configure} next run, they include the new directory.

@item
Add the new test case to the directory, as above. 

@item
To add support in the new directory for configure and make, you must
also create a @code{Makefile.in} and a @code{configure.in}.  @xref{What
Configure Does,,What Configure Does, configure.info, Cygnus Configure}.
@end enumerate

@c FIXME! Expand this sentence to at least a section, maybe a chapter...
@c The @file{admin} directory contains templates for a few common forms
@c of test.

@node Hints
@section Hints on writing a test case
@cindex hints on test case writing

There may be useful existing procedures already written for your test in
the @file{lib} directory of the DejaGnu distribution.  @xref{DejaGnu
Builtins,,DejaGnu Builtins}.

It is safest to write patterns that match @emph{all} the output
generated by the tested program; this is called @dfn{closure}.  If a
pattern does not match the entire output, any output that remains will
be examined by the @emph{next} @code{expect} command.  In this
situation, the precise boundary that determines which @code{expect}
command sees what is very sensitive to timing between the @code{expect}
task and the task running the tested tool.  As a result, the test may
sometimes appear to work, but is likely to have unpredictable results.
(This problem is particularly likely for interactive tools, but can also
affect batch tools---especially for tests that take a long time to finish.)
The best way to ensure closure is to use the @samp{-re} option for the
@code{expect} command to write the pattern as a full regular
expressions; then you can match the end of output using a @samp{$}.  It
is also a good idea to write patterns that match all available output by
using @samp{.*\} after the text of interest; this will also match any
intervening blank lines.  Sometimes an alternative is to match end of
line using @samp{\r} or @samp{\n}, but this is usually too dependent on
terminal settings.
@c FIXME!! explain what "end of output" means for interactive task.
@c (Timeout or EOF, right?)

Always escape punctuation, such as @samp{(} or @samp{"}, in your
patterns; for example, write @samp{\(}.  If you forget to escape
punctuation, you will usually see an error message like @samp{extra
characters after close-quote}.

If you have trouble understanding why a pattern does not match the
program output, try using the @samp{--debug} option to @code{runtest},
and examine the debug log carefully.  @xref{Debug,,Debug Log}.  

Be careful not to neglect output generated by setup rather than by the
interesting parts of a test case.  For example, while testing @sc{gdb},
I issue a send @samp{set height 0\n} command.  The purpose is simply to
make sure @sc{gdb} never calls a paging program.  The @samp{set height}
command in @sc{gdb} does not generate any output; but running @emph{any}
command makes @sc{gdb} issue a new @samp{(gdb) } prompt.  If there were
no @code{expect} command to match this prompt, the output @samp{(gdb) }
begins the text seen by the next @code{expect} command---which might
make @emph{that} pattern fail to match.

To preserve basic sanity, I also recommended that no test ever pass if
there was any kind of problem in the test case.  To take an extreme
case, tests that pass even when the tool will not spawn are misleading.
Ideally, a test in this sort of situation should not fail either.
Instead, print an error message by calling one of the DejaGnu procedures
@code{error} or @code{warning}.

@node Variables
@section Special variables used by test cases
@cindex special variables

@cindex variables for all tests
Your test cases can use these variables, with conventional meanings (as
well as the variables saved in @file{site.exp}
@pxref{Customizing,,Setting @code{runtest} defaults}):

@quotation
@emph{These variables are available to all test cases.}
@end quotation

@ftable @code
@item prms_id
@cindex PRMS bug number
@cindex GNATS bug number
@cindex bug number
The tracking system (e.g. @sc{gnats}) number identifying a corresponding
bugreport.  (@samp{0} if you do not specify it in the test script.)

@item bug_id
@cindex bug number, extra
An optional bug id; may reflect a bug identification from another
organization.  (@samp{0} if you do not specify it.)

@item subdir
@cindex current test subdirectory
The subdirectory for the current test case.
@end ftable

@quotation
@emph{These variables should never be changed. They appear in most
tests.}
@end quotation

@ftable @code
@item expect_out(buffer)
@cindex last command output
The output from the last command. This is an internal variable set by
@code{expect}. 

@item exec_output
This is the output from a @code{@var{tool}_load} command. This only
applies to tools like @sc{gcc} and @sc{gas} which produce an object
file that must in turn be executed to complete a test.

@item comp_output
This is the output from a @code{@var{tool}_start} command.  This is
conventionally used for batch oriented programs, like @sc{gcc} and
@sc{gas}, that may produce interesting output (warnings, errors) without
further interaction.
@end ftable

@node Extending
@chapter New Tools, Targets, or Hosts 

The most common ways to extend the DejaGnu framework are: adding a suite
of tests for a new tool to be tested; adding support for testing on a
new target; and porting @code{runtest} to a new host.

@menu
* Adding Tools::                How to add tests for a new tool
* Adding Targets::              How to add a new target
* Porting::                     Porting DejaGnu to a new host
@end menu

@node Adding Tools
@section Writing tests for a new tool

In general, the best way to learn how to write (code or even prose) is
to read something similar.  This principle applies to test cases and to
test suites.  Unfortunately, well-established test suites have a way of
developing their own conventions: as test writers become more
experienced with DejaGnu and with Tcl, they accumulate more utilities,
and take advantage of more and more features of @code{expect} and Tcl in
general.

Inspecting such established test suites may make the prospect of
creating an entirely new test suite appear overwhelming.  Nevertheless,
it is quite straightforward to get a new test suite going.

@cindex Lupton, Robert
There is one test suite that is guaranteed not to grow more elaborate
over time: both it and the tool it tests were created expressly to
illustrate what it takes to get started with DejaGnu.  The
@file{example/} directory of the DejaGnu distribution contains both an
interactive tool called @code{calc}, and a test suite for it.  Reading
this test suite, and experimenting with it, is a good way to supplement
the information in this section.  (Thanks to Robert Lupton for creating
@code{calc} and its test suite---and also the first version of this
section of the manual!)

To help orient you further in this task, here is an outline of the steps
to begin building a test suite for a program @var{example}.

@enumerate
@item
Create or select a directory to contain your new collection of tests.
Change to that directory (shown here as @code{testsuite}):

@example
eg$ cd testsuite/
@end example

@item
Create a @file{configure.in} file in this directory, to control
configuration-dependent choices for your tests.  So far as DejaGnu is
concerned, the important thing is to set a value for the variable
@code{target_abbrev}; this value is the link to the init file you will
write soon.  (For simplicity, we assume the environment is Unix, and use
@samp{unix} as the value.)

What else is needed in @file{configure.in} depends on the requirements
of your tool, your intended test environments, and which
@code{configure} system you use.  This example is a minimal
@code{configure.in} for use with Cygnus Configure.  (For an alternative
based on the FSF @code{autoconf} system, see the @code{calc} example
distributed with DejaGnu.)  Replace @var{example} with the name of your
program:

@cartouche
@smallexample
# This file is a shell script fragment
# for use with Cygnus configure.

srctrigger="@var{example}.0"
srcname="The DejaGnu @var{example} tests"

# per-host:

# per-target:

# everything defaults to unix for a target
target_abbrev=unix

# post-target:

@end smallexample
@end cartouche

@item
Create @file{Makefile.in}, the source file used by @code{configure} to
build your @file{Makefile}.  Its leading section should as usual contain
the values that @code{configure} may override:

@cartouche
@smallexample
srcdir = .
prefix = /usr/local

exec_prefix = $(prefix)
bindir = $(exec_prefix)/bin
libdir = $(exec_prefix)/lib
tooldir = $(libdir)/$(target_alias)

datadir = $(exec_prefix)/lib/dejagnu

RUNTEST = runtest
RUNTESTFLAGS =
FLAGS_TO_PASS =

#### host, target, site specific Makefile frags come in here.
@end smallexample
@end cartouche

This should be followed by the standard targets at your site.  To begin
with, they need not do anything---for example, these definitions will
do:

@cartouche
@smallexample

all:

info:

install-info:

install:
uninstall:

clean:
        -rm -f *~ core *.info*

@end smallexample
@end cartouche

It is also a good idea to make sure your @file{Makefile} can rebuild
itself if @file{Makefile.in} changes, with a target like this (which
works for either Cygnus or FSF Configure):

@cartouche
@smallexample
Makefile : $(srcdir)/Makefile.in $(host_makefile_frag) \
             $(target_makefile_frag)
        $(SHELL) ./config.status
@end smallexample
@end cartouche

You also need to include two targets important to DejaGnu: @code{check},
to run the tests, and @code{site.exp}, to set up the Tcl copies of
configuration-dependent values.  The @code{check} target must run
@samp{runtest --tool @var{example}}:

@cartouche
@smallexample
check: site.exp all
        $(RUNTEST) $(RUNTESTFLAGS) $(FLAGS_TO_PASS) \
            --tool @var{example} --srcdir $(srcdir) 
@end smallexample
@end cartouche

The @code{site.exp} target should usually set up (among other things!) a
Tcl variable for the name of your program:

@cartouche
@smallexample
site.exp: ./config.status Makefile
        @@echo "Making a new config file..."
        -@@rm -f ./tmp?
        @@touch site.exp

        -@@mv site.exp site.bak
        @@echo "## these variables are automatically\
 generated by make ##" > ./tmp0
        @@echo "# Do not edit here. If you wish to\
 override these values" >> ./tmp0
        @@echo "# add them to the last section" >> ./tmp0
        @@echo "set host_os $@{host_os@}" >> ./tmp0
        @@echo "set host_alias $@{host_alias@}" >> ./tmp0
        @@echo "set host_cpu $@{host_cpu@}" >> ./tmp0
        @@echo "set host_vendor $@{host_vendor@}" >> ./tmp0
        @@echo "set target_os $@{target_os@}" >> ./tmp0
        @@echo "set target_alias $@{target_alias@}" >> ./tmp0
        @@echo "set target_cpu $@{target_cpu@}" >> ./tmp0
        @@echo "set target_vendor $@{target_vendor@}" >> ./tmp0
        @@echo "set host_triplet $@{host_canonical@}" >> ./tmp0
        @@echo "set target_triplet $@{target_canonical@}">>./tmp0
        @@echo "set tool binutils" >> ./tmp0
        @@echo "set srcdir $@{srcdir@}" >> ./tmp0
        @@echo "set objdir `pwd`" >> ./tmp0
        @@echo "set @var{examplename} @var{example}" >> ./tmp0
        @@echo "## All variables above are generated by\
 configure. Do Not Edit ##" >> ./tmp0
                @@cat ./tmp0 > site.exp
        @@sed < site.bak \
               -e '1,/^## All variables above are.*##/ d' \
               >> site.exp
        -@@rm -f ./tmp?
@end smallexample
@end cartouche

@item
Create a directory (in @file{testsuite/}) called @file{config/}:

@example
eg$ mkdir config
@end example

@item
Make an init file in this directory; its name must start with the
@code{target_abbrev} value, so call it @file{config/unix.exp}.  
This is the file that contains the target-dependent procedures;
fortunately, most of them do not have to do very much in order for
@code{runtest} to run.

If @var{example} is not interactive, you can get away with this minimal
@file{unix.exp} to begin with:

@cartouche
@smallexample
proc foo_exit @{@} @{@}
proc foo_version @{@} @{@}
@end smallexample
@end cartouche

If @var{example} is interactive, however, you might as well define a
start routine @emph{and invoke it} by using an init file like this:

@cartouche
@smallexample
proc foo_exit @{@} @{@}
proc foo_version @{@} @{@}

proc foo_start @{@} @{
  global @var{examplename}
  spawn $@var{examplename}
  expect @{
    -re "" @{@}
  @}
@}
foo_start
@end smallexample
@end cartouche

@item
Create a directory whose name begins with your tool's name, to contain
tests:

@example
eg$ mkdir @var{example}.0
@end example

@item
Create a sample test file in @file{@var{example}.0}.  Its name must end
with @samp{.exp}; you can use @samp{first-try.exp}  To begin with, just
write there a line of Tcl code to issue a message:

@cartouche
@smallexample
send_user "Testing: one, two...\n"
@end smallexample
@end cartouche

@item
Back in the @file{testsuite/} (top level) directory, run

@example
eg$ configure
@end example

(You may have to specify more of a path, if a suitable @code{configure}
is not available in your execution path.)

@item
You are now ready to triumphantly type @samp{make check} or
@samp{runtest --tool @var{example}}.  You should see something like this:

@cartouche
@smallexample
Test Run By rhl on Fri Jan 29 16:25:44 EST 1993

                === @var{example} tests ===

Running ./@var{example}.0/first-try.exp ...
Testing: one, two...

                === @var{example} Summary ===

@end smallexample
@end cartouche

There is no output in the summary, because so far the example does not
call any of the procedures that establish a test outcome.

@item
Begin writing some real tests.  For an interactive tool, you should
probably write a real exit routine in fairly short order; in any case,
you should also write a real version routine soon.
@end enumerate

@node Adding Targets
@section Adding a target
@cindex adding a target

DejaGnu has some additional requirements for target support, beyond the
general-purpose provisions of Cygnus @code{configure}.  @code{runtest}
must actively communicate with the target, rather than simply generating
or managing code for the target architecture.  Therefore, each tool
requires an initialization module for each target.  For new targets, you
must supply a few Tcl procedures to adapt DejaGnu to the target.  This
permits DejaGnu itself to remain target independent.  @xref{Init
Module,,Initialization module}, for a discussion of the naming
conventions that enable DejaGnu to locate and use init files.

Usually the best way to write a new initialization module is to edit an
existing initialization module; some trial and error will be required.
If necessary, you can use the @samp{--debug} option to see what
is really going on.

When you code an initialization module, be generous in printing
information controlled by the @code{verbose} procedure (@pxref{DejaGnu
Builtins, DejaGnu procedures}).

Most of the work is in getting the communications right. Communications
code (for several situations involving IP networks or serial lines) is
available in a DejaGnu library file, @file{lib/remote.exp}.
@xref{DejaGnu Builtins,,DejaGnu Builtins}. 

@c FIXME!  Say something about Tcl debugger here.
If you suspect a communication problem, try running the connection
interactively from @code{expect}.  (There are three ways of running
@code{expect} as an interactive interpreter.  You can run @code{expect}
with no arguments, and control it completely interactively; or you can
use @samp{expect -i} together with other command-line options and
arguments; or you can run the command @code{interpreter} from any
@code{expect} procedure.  Use @code{return} to get back to the calling
procedure (if any), or @code{return -tcl} to make the calling procedure
itself return to its caller; use @code{exit} or end-of-file to leave
@code{expect} altogether.)  Run the program whose name is recorded in
@samp{$connectmode}, with the arguments in @samp{$targetname}, to
establish a connection.  You should at least be able to get a prompt
from any target that is physically connected.

@node Porting
@section Porting to a new host
@cindex porting to a new host

The task of porting DejaGnu is basically that of porting Tcl and
@code{expect}. Tcl and @code{expect}, as distributed with DejaGnu, both
use @code{autoconf}; they should port automatically to most Unix
systems.

Once Tcl and @code{expect} are ported, DejaGnu should run.  Most system
dependencies are taken care of by using @code{expect} as the main
command shell.

@node Installation
@appendix Installing DejaGnu

@cindex host, explained
@cindex target, explained
@cindex DejaGnu configuration
@cindex configuring DejaGnu
Once you have the DejaGnu source unpacked and available, you must first
configure the software to specify where it is to run (and the associated
defaults); then you can proceed to installing it.

@menu
* Configuring DejaGnu::
* Installing DejaGnu::
@end menu

@node Configuring DejaGnu
@section Configuring the DejaGnu test driver

It is usually best to configure in a directory separate
from the source tree, specifying where to find the source with the
optional @samp{--srcdir} option to @code{configure}. DejaGnu uses the
GNU @code{autoconf} to configure itself. For more info on using
autoconf, read the GNU autoconf manual. To configure, execute the
@file{configure} program, no other options are required. For an example,
to configure in a seperate tree for objects, execute the configure
script from the source tree like this:

@smallexample
../dejagnu-1.3/configure
@end smallexample

DejaGnu doesn't care at config time if it's for testing a native system
or a cross system. That is determined at runtime by using the config
files.

@cindex @code{prefix}, configure options
@cindex @code{exec_prefix}, configure options.
You may also want to use the @code{configure} option @samp{--prefix} to
specify where you want DejaGnu and its supporting code installed.  By
default, installation is in subdirectories of @file{/usr/local}, but you
can select any alternate directory @var{altdir} by including
@samp{--prefix=@var{altdir}} on the @code{configure} command line.
(This value is captured in the Makefile variables @code{prefix}
and @code{exec_prefix}.)

@cindex auxiliary programs
@cindex test suite distributions
@cindex @code{make} builds part of tests
Save for a small number of example tests, the DejaGnu distribution
itself does not include any test suites; these are available separately.
Test suites for the @sc{gnu} compiler (testing both GCC and G++) and for
the @sc{gnu} binary utilities are distributed in parallel with the
DejaGnu distribution (but packaged as separate files).  The test suite
for the @sc{gnu} debugger is distributed in parallel with each release
of GDB itself, starting with GDB 4.9.  After configuring the top-level
DejaGnu directory, unpack and configure the test directories for the
tools you want to test; then, in each test directory, run @code{make} to
build auxiliary programs required by some of the tests.

@node Installing DejaGnu
@section Installing DejaGnu

@cindex installing DejaGnu
To install DejaGnu in your filesystem (either in @file{/usr/local}, or
as specified by your @samp{--prefix} option to @code{configure}), execute

@example
eg$ make install
@end example

@noindent
@samp{make install} does these things for DejaGnu:

@enumerate
@item
Look in the path specified for executables (@file{$exec_prefix}) for
directories called @file{lib} and @file{bin}.  If these directories do
not exist, @samp{make install} creates them.

@item
Create another directory in the @file{lib} directory, called
@file{dejagnu}.

@item
Copy the @code{runtest} shell script into @file{$exec_prefix/bin}.

@item
Copy all the library files (used to support the framework) into
@file{$exec_prefix/lib/dejagnu}.

@item
Copy @file{runtest.exp} into @file{$exec_prefix/lib/dejagnu}.  This is
the main Tcl code implementing DejaGnu.

@end enumerate

Each test suite collection comes with simple installation instructions
in a @file{README} file; in general, the test suites are designed to be
unpacked in the source directory for the corresponding tool, and extract
into a directory called @file{testsuite}.

@node Index
@unnumbered Index

@printindex cp

@contents

@bye
