Re: How to parse UNIX commands ...

You can as well use perl at command line to evaluate UNIX command
output:

df -k | perl -ane 'print "$F[5]\n" if($F[5])'


T Baetzler wrote:
Hi,

benbart@xxxxxxxxxxxx asked:
How do I parse or evaluate the output of UNIX commands?

For example, in UNIX scripts, I can run filesystem=`df -k |
awk -F"" ' { print
$6 }'` to check for the mount points.

How do I achieve the same in Perl? That is, I tried:

Essentially in the same way - i.e. "my $x = `df -k`".

Maybe I can just simply run system 'df -k', re-direct that
into some output file and then parse it using OPEN-CLOSE
filehandles. Is there any easier way of doing this?

Yes, like this:

open( FH, '-|', 'df -k' ) or die "error: $!";

while( my $line = <FH> ){
# parse df output here
}

close( FH ) or die "error: $!";

I really recommend that you read the sections about open()
in the perlipc manpage. Lots of good stuff there!

HTH,
Thomas

.

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