Dear fellow monks,
I'm calling a unix command from my Perl script and like to avoid any text going the STDERR or STDOUT coming from the command. So I just added a &>/dev/null to the system string like I know it from the BASH shell prompt.
To my surprise this doesn't work, I still get the STDERR on the calling shell: 

system("dd if=/dev/zero of=$SIZE bs=1M count=0 seek=$SIZEMB &>/dev/nul
+l})';
# prints to STDERR:
10+0 records in
10+0 records out
10485760 bytes (10 MB) copied, 0.00426433 s, 2.5 GB/s

[download]

If I now change the "&>" - which affects STDOUT and STDERR - to "2>" - which only affects STDERR - it works: 

system("dd if=/dev/zero of=$SIZE bs=1M count=0 seek=$SIZEMB &>/dev/nul
+l})';
# prints nothing

[download]

Why is this? It's not a problem but I like to know it anyway. The redirect is handled by the shell (==calling shell (BASH)?) not by perl, isn't it? Please enlighten me.

PS: The dd command is used to create a sparse file. Does someone know how to create sparse files with Perl without using a system command?

In reply to system and &>/dev/null by mscharrer

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