STDERR and STDOUT can be localized, like any other global file handle, . That done you can call your function and output will go to the new handle. In perl 5.8, 

my ($errors, $output);
sub foo {
    print STDERR "Something to worry about\n";
}

{
    open local(*STDERR), '>', \$errors;
    foo();
}

warn "STDERR ought to be restored now";
$errors =~ s/Something/Nothing/;
print $errors;

[download]
That takes 5.8+ because of the PerlIO trick of opening a file to memory by using a reference to a scalar in the filename slot. In pre-5.8 perls, you can use IO::Scalar or IO::Stringy for the same purpose.

After Compline,
Zaxo

In reply to Re: How to capture STDOUT/STDERR of a function by Zaxo
in thread How to capture STDOUT/STDERR of a function by johnnywang

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