how to capture bash errors like 'command not found' from Perl backticks

[Isaac Ho]

Hi, I've read the perlfaq on capturing stderr from an external
command. However, I cannot seem to get it to capture ALL error
messages. In particular, if the command I'm trying to run externally
fails due to 'command not found' at the shell level, I cannot capture
it with the methods listed.

For instance:

use strict;
use IPC::Open3;
use Symbol qw(gensym);

my $cmd="bogus";
my $pid=open3(gensym, ">&STDERR", \*PH, $cmd );
while( <PH> ) { print $_ }
waitpid( $pid, 0 );

This runs the command "bogus", which fails when I run it by hand as:

-bash: bogus: command not found


however, running the above wrapper perl script gives:

open3: exec of bogus failed at test.pl line 7

which is too generic of a message to be useful for me.

When I run:

bogus 2> temp.err
cat temp.err

Then it does capture the stderr but I'd like to not have to write temp
files like this, since I am running commands in a pipeline context...

Thanks,

Isaac