NAME

IO::Capture::ErrorMessages - Capture output from STDERR and warn()

SYNOPSYS

    # Generic example (Just to give the overall view)
    use IO::Capture::Stderr;

    my $capture = IO::Capture::ErrorMessages->new();
    $capture->start();
    print STDERR "Test Line One\n";
    print STDERR "Test Line Two\n";
    print STDERR "Test Line Three\n";
    warn "Test line Four\n";
    $capture->stop();

    $line = $capture->read;
    print "$line";         # prints "Test Line One"

    $line = $capture->read;
    print "$line";         # prints "Test Line Two"

    $capture->line_pointer(4);

    $line = $capture->read;
    print "$line";         # prints "Test Line Four"

    $current_line_position = $capture->line_pointer;

    # More useful example 1 - "Using in module tests"
    #  Note: If you don't want to make users install 
    #        the IO::Capture module just for your tests,
    #        you can just install in the t/lib directory
    #        of your module and use the lib pragma in  
    #        your tests. 

    use lib "t/lib";
    use IO::Capture:ErrorMessages;

    use Test::More;

    my $capture =  IO::Capture:ErrorMessages->new;
    $capture->start

    # execute with a bad parameter to make sure get
    # an error.

    ok( ! $test("Bad Parameter") );

    $capture->stop();

    # More useful example 2 - "Use with GUI like Tk"
    #   If you are calling a CPAN module that may
    # print some messages that you don't want going
    # to the shell window, or being lost, you can 
    # capture them and then put to a log file or
    # print in a text frame

    

DESCRIPTION

The module IO::Capture::Stderr, is derived from the abstract class in IO::Capture. IO::Capture It captures all output sent to STDERR, and installs a signal handler to capture the output sent via the warn() function. (And friends - Such as carp()) We primarily use it in module tests, where the test will cause some warning to be printed. To keep the output from cluttering up the nice neat row of 'ok's. ;-)

Note: This module won't work with the perl function, system(), or any other operation involing a fork(). If you want to capture the output from a system command, it is faster to use open() or backticks.

       my $output = `/usr/sbin/ls -l 2>&1`;

METHODS

AUTHORS

Mark Reynolds reynolds@sgi.com

Jon Morgan jmorgan@sgi.com

COPYRIGHT

Copyright (c) 2003, Mark Reynolds and Jon Morgan. All Rights Reserved. This module is free software. It may be used, redistributed and/or modified under the same terms as Perl itself.