First off, for the case of catching STDERR when running another program, check out IPC::Open3, which has been in the standard perl distribution for years.

In the case of running other perl code and capturing the standard error output from it, say your second case above, you can do something like this in perl 5.8 and higher:

open my $savederr, '>&', \*STDERR;
my $module_stderr = '';
open(STDERR, '>', \$module_stderr);
SomeFunkyModule::sub_that_spews_to_stderr();
open(STDERR, '>&', $savederr);
# process the stuff in $module_stderr

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In older perls, you can do the same thing with IO::String.

--
@/=map{[/./g]}qw/.h_nJ Xapou cets krht ele_ r_ra/;
map{y/X_/\n /;print}map{pop@$_}@/for@/

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In reply to Re: capturing output from open | by fizbin
in thread capturing output from open | by DrWhy

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