#!/usr/bin/perl -w
use strict;
system("echo foo");

##</code><code>##

#!/usr/bin/perl -w
use strict;
my $res = system("/sys/command");

##</code><code>##

#!/usr/bin/perl -w
use strict;
my $res = `/sys/command`;

##</code><code>##

#!/usr/bin/perl -w
use strict;
my $file_handle;
open $file_handle, "/sys/command |" or die "unable to open command as pipe";

while my $line = ( <$file_handle> ) {
     chomp $line; # remove new line
     do_something( $line );
}