Creating a Process Table hash in Perl


I came across a situation where I needed to access the process table in Perl. The problem that i found was that the best accessor Proc::ProcessTable only retrieved an array. Since it seems fairly senseless to keep looping over an array to find the exact process id that I want, you may want to turn it into a hash.

use strict;
use warnings;
use Proc::ProcessTable;

 # Create a new process table object
 my ($pt) = new Proc::ProcessTable;

 # Initialize your process table hash
 my (%pt_hash);

 # Get the fields that your architecture supports
 my (@fields) = $pt->fields;

 # Outer loop for each process id
 foreach my $proc ( @{$pt->table} ) {
    # Inner loop for each field within the process id
    for my $field (@fields) {
       # Add the field to the hash
       $pt_hash{$proc->pid}{$field} = $proc->$field();

It’s just as simple as that. If you want to be sure that its in there. At the end of the file add these two lines for proof:

use Data::Dumper;
print Dumper \%pt_hash;

The hash is organized with the keys being the process ids. There is another hash underneath it with all the fields as hash keys.

One Response to “Creating a Process Table hash in Perl”

  1. georgepalli says:

    I prefer this

    foreach my $proc ( @{$pt->table} )
    $pt_hash{$proc->pid} = $proc;

    Either way – you access the elements by


    And you don't need to initialize @fields

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