Open a pipe to the who command : Open file « File « Perl






  1. Perl
  2. File
  3. Open file

Open a pipe to the who command

    

#!/usr/bin/perl


use strict; 
my %who;   

open (WHOFH,"who |") or die "Can't open who: $!"; 

while (<WHOFH>) { 
    next unless /^(\S+)/; 
    $who{$1}++; 
} 

foreach (sort {$who{$b}<=>$who{$a}} keys %who) { 
    printf "%10s %d\n",$_,$who{$_}; 
}

close WHOFH or die "Close error: $!";








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