I generally recommend people to try to avoid parsing the output of another program when the information they require can be obtained more directly from other sources. For example, another way which may prove to be a better alternative for obtaining the uptime would be to source if directly from /proc/uptime (assuming that this interface is available to you) - This allows for vagarities of uptime output and regular pattern matching to sidestepped altogether.

For example:

use Date::Calc qw/ Normalize_DHMS /;
use IO::File;

#   get_uptime function - returns uptime from /proc/uptime
#   as 4-member array representing current system uptime in
#   days, hours, minutes and seconds

sub get_uptime {
    my $uptime;
    my $fh = IO::File->new('/proc/uptime', 'r');
    $uptime = (split /\s+/, <$fh>)[0] if defined $fh;
    return Normalize_DHMS(0, 0, 0, $uptime) if defined $uptime;
}

[download]

A similar approach could be taken to obtain load average information from /proc/loadavg.

 

In reply to Re: Parsing 'uptime' output by rob_au
in thread Parsing 'uptime' output by Anonymous Monk

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