Getting STDOUT, STDERR, and response code from external *nix command in perl

Question

I want to execute an external command from within my Perl script, putting the output of both stdout and stderr into a $variable of my choice, and to get the com

Answer 1

STDERR is intended to be used for errors or messages that might need to be separated from the STDOUT output stream. Hence, I would not expect any STDERR from the output of a command like less.

If you want both (or either) stream and the return code, you could do:

my $out=qx($cmd 2>&1);
my $r_c=$?
print "output was $out\n";
print "return code = ", $r_c == -1 ? $r_c : $r_c>>8, "\n";

If the command isn't executable (perhaps because you meant to use less but wrote lsss instead), the return code will be -1. Otherwise, the correct exit value is the high 8-bits. See system.