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Think about Loose Coupling
 
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As suggested by Laurent R, you might consider using more Perl and less files and system commands.

If you like terse, you might try something like:

use strict; use warnings; my $cmd = "/usr/sbin/ntpq -p"; my $offset = (split(/\s+/, (grep(/^\*/, `$cmd`))[0]))[8]; print "$offset\n";

If you find that a bit difficult to read and would prefer several statements with intermediate variables, you might try something like:

use strict; use warnings; my $cmd = "/usr/sbin/ntpq -p"; my @ntpout = `$cmd`; my $current_time_source = (grep(/^\*/, @ntpout))[0]; my $offset = (split(/\s+/, $current_time_source))[8]; print "$offset\n";

You should also think about what will happen if there are errors or unexpected situations. You might change the latter to something like:

use strict; use warnings; my $cmd = "/usr/sbin/ntpq -p"; my @ntpout = `$cmd`; die "$cmd failed with: $^E, $?" unless(@ntpout); my $current_time_source = (grep(/^\*/, @ntpout))[0]; die "Not synchronized" unless($current_time_source); my $offset = (split(/\s+/, $current_time_source))[8]; die "$current_time_source: No offset" unless(defined($offset)); print "$offset\n";

In reply to Re: using Backtick inside perl gives different output by ig
in thread using Backtick inside perl gives different output by kaka_2

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