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#!/usr/bin/perl -w
## Demonstration of chatting with a bash shell.
use strict;
use IPC::Run qw( start pump finish timeout );
my ( $in, $out, $err );
my $h = start(
[qw(sh -login -i )], \$in, \$out, \$err,
debug => 0,
timeout(5),
);
## The first thing we do is to convert the user's prompt. Normally, we would
## do a '' as the first command in the for () loop so we could detect errors
## that bash might emit on startup. In this case, we need to do this
## initialization first so that we have a prompt to look for so we know that
## it's ready to accept input. This is all because the startup scripts
## that bash runs set PS1, and we can't have that.
$in = "PS1='<PROMPT> '\n";
## bash prompts on stderr. Consume everything before the first
## <PROMPT> (which is the second prompt bash issues).
pump $h until $err =~ s/.*(?=^<PROMPT> (?!\n)\Z)//ms;
for (qw( ls ps fOoBaR pwd )) {
$in = $_ . "\n";
$out = '';
pump $h until $err =~ s/\A(<PROMPT> .*)(?=^<PROMPT> (?!\n)\Z)//ms;
print map { "sh err: $_\n" } split( /\n/m, $1 );
print map { "sh: $_\n" } split( /\n/m, $out );
}
finish $h ;