Crontab/Perl piping magic [duplicate]

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Possible Duplicate:
In the bash shell, what is “ 2>&1 ”?

I recently saw this in a crontab:

5 * * * * perl /abs/path/to/my/script.pl >> /abs/path/two/my/script-log.txt 2>&1

If I'm reading this correctly, it runs script.pl every hour, 5 minutes after the hour (so 2:05, 3:05, 10:05, etc.). Again, if I'm correct, it is redirecting standard output to a log file located elsewhere.

But what is this Linux/Perl voo-doo at the end of the crontab?

2>&1

What is this instructing Linux/Perl to do? And if my above interpretation of the crontab is incorrect, please clarify for me as well! Thanks in advance!

Answer 1

Redirect file descriptor 2 (stderr) over 1; it's the idiomatic way to tell /bin/sh that stderr should go in the same place as stdout

Answer 2

It's bourne shell syntax to associate file descriptor 2 (STDERR) with file descriptor 1 (STDOUT), in effect sending STDERR to /abs/path/two/my/script-log.txt.