awk usage in perl scripting - perl

Question

Hi am writing a script which its need to grep the 6th column of the output using awk command but am getting other output.
What is the exact syntax in perl to extract 6th column using awk?
#!/usr/bin/perl
use strict;
use warnings;
use diagnostics;
my $filesystem=`df -h |grep -i dev|grep -vE '^Filesystem|proc|none|udev|tmpfs'`;
print "(\"$filesystem\"|awk '{print \$6}')"
Output :
7831c1c4be8c% ./test.pl
("/dev/disk1 112Gi 43Gi 69Gi 39% 11227595 18084674 38% /
devfs 183Ki 183Ki 0Bi 100% 634 0 100% /dev
"|awk '{print $6}')%
Am trying to remove the % how it can be done ?
7831c1c4be8c% cat test.pl
#!/usr/bin/perl
use warnings;
use strict;
open my $FS, q(df -h |) or die $!;
while (<$FS>) {
print +(split)[4], "\n"
if /dev/i and not /devfs/;
}
7831c1c4be8c% ./test.pl
40%

Answer 1

You don't need awk inside Perl.
#!/usr/bin/perl
use warnings;
use strict;
open my $FS, '-|', q(df -h) or die $!;
while (<$FS>) {
print +(split)[5], "\n"
if /dev/i and not /^Filesystem|proc|none|udev|tmpfs/;
}

Answer 2

as the previous answer says, you don't need awk or grep system calls in perl. however, I will tell you that one reason your code isn't working is because you never made the awk system call. print does not execute the system call. you would have to use system() to execute it.
anyway fwiw you can also do what you want in a one-liner like so:
df -h | perl -lnae 'next if $F[0] =~ /regex/; print $F[5]'