IO::Capture::Stdout - Capture any output sent to STDOUT
use IO::Capture::Stdout; $capture = IO::Capture::Stdout->new(); $capture->start(); # STDOUT Output captured print STDOUT "Test Line One\n"; print STDOUT "Test Line Two\n"; print STDOUT "Test Line Three\n"; $capture->stop(); # STDOUT output sent to wherever it was before 'start' # In 'scalar context' returns next line $line = $capture->read; print "$line"; # prints "Test Line One" $line = $capture->read; print "$line"; # prints "Test Line Two" # move line pointer to line 1 $capture->line_pointer(1); $line = $capture->read; print "$line"; # prints "Test Line One" # Find out current line number $current_line_position = $capture->line_pointer; # In 'List Context' return an array(list) @all_lines = $capture->read;
The module IO::Capture::Stdout, is derived from the abstract class IO::Capture. See IO::Capture. The purpose of the module (as the name suggests) is to capture any output sent to STDOUT. After the capture is stopped, the STDOUT filehandle will be reset to the previous location. E.g., If previously redirected to a file, when IO::Capture->stop is called, output will start going into that file again.
IO::Capture::Stdout
IO::Capture
STDOUT
IO::Capture->stop
Creates a new capture object.
An object can be reused as needed, so will only need to do one of these.
Be aware, any data previously captured will be discarded if a new capture session is started.
Start capturing data into the IO::Capture Object.
Can not be called on an object that is already capturing.
Can not be called while STDOUT tied to an object.
undef will be returned on an error.
undef
Stop capturing data and point STDOUT back to it's previous output location I.e., untie STDOUT
In Scalar Context
Lines are read from the buffer at the position of the line_pointer, and the pointer is incremented by one.
line_pointer
$next_line = $capture->read;
In List Context
The array is returned. The line_pointer is not affected.
@buffer = $capture->read;
Data lines are returned exactly as they were captured. You may want to use chomp on them if you don't want the end of line character(s)
chomp
while (my $line = $capture->read) { chomp $line; $cat_line = join '', $cat_line, $line; }
Reads or sets the line_pointer.
my $current_line = $capture->line_pointer; $capture->line_pointer(1);
If you would like to sub-class this module to add a feature (method) or two, here is a couple of easy steps. Also see IO::Capture::Overview.
Give your package a name
package MyPackage;
Use this IO::Capture::Stdout as your base class like this:
package MyPackage; use base qw/IO::Capture::Stdout/;
Add your new method like this
package MyPackage; use base qw/IO::Capture::Stdout/; sub grep { my $self = shift; for $line ( }
IO::Capture::Overview
IO::Capture::Stderr
IO::Capture::ErrorMessages
Mark Reynolds reynolds@sgi.com
Jon Morgan jmorgan@sgi.com
Copyright (c) 2003, Mark Reynolds. All Rights Reserved. This module is free software. It may be used, redistributed and/or modified under the same terms as Perl itself.
To install IO::Capture, copy and paste the appropriate command in to your terminal.
cpanm
cpanm IO::Capture
CPAN shell
perl -MCPAN -e shell install IO::Capture
For more information on module installation, please visit the detailed CPAN module installation guide.