Hi monks, been a while since I was here. Good to be back. Before I say anymore, I know about backticks and qx and capturing STDOUT/STDERR so please don't post a response about that. Below is what I want to do (in simplified form). It seems to me it should work (i.e. catch stdout <and likewise if my example had it, catch stderr too>). I mean isn't system() just doing a fork/execvp? Shouldn't it inherit my file descriptors (in this case the one pointing to an in memory file)? I want to do it this way so that I can catch the return codes as well as the stderr/stdout of a failed command. 
#!/usr/bin/perl

@callout = qw( echo foo );

open(my $old_stdout,">&STDOUT");
close(STDOUT);
my $stdout;
open(STDOUT,">",\$stdout);

my $system_return_value = system(@callout);

close(STDOUT);
open(STDOUT,">&",$old_stdout);
close($old_stdout);

print "captured: $stdout\n"; # debug

unless ( $system_return_value == 0 ) {
#... do some stuff, look at return code (shift by 8), 
# print stdout/stderr of 
# failed command to log, etc, etc.
}

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In reply to catching STDERR of a system(@callout) by agarsha

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