Is there a direct way to redirect what would go to STDOUT and STDERR to variables

Yes, you can open STDOUT/STDERR to $variables. For example 

my $script_content = 'print STDERR "foo"';

open(SAVEERR, ">&STDERR");
close(STDERR);
open(STDERR, '>', \my $buf) or die $!;

eval $script_content;

print "buf = $buf\n";    # "buf = foo"

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But note that this technique does not capture what external programs further down the line might write to stderr (just in case that's what you're having in mind).

I.e., if $script_content was something like 'system "cat does-not-exist"', $buf would not hold cat's error message "cat: does-not-exist: No such file or directory". Reason is that file handles opened to scalar variables are Perl-internal (indicated by fileno returning -1), not accessible from processes outside of the Perl program.

In reply to Re: Reassign STDOUT/STDERR contents to a variable by almut
in thread Reassign STDOUT/STDERR contents to a variable by lothos

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