in reply to Parent process name

You mean something along the lines of: 

  #!/usr/bin/perl 

  use strict;
  use warnings;

  my $parent_id;

  foreach (`ps -ef`) {
     my ($uid,$pid,$ppid) = split;
     next unless ($pid eq $$);
     $parent_id = $ppid;
     last;
  }

  my $parent = (grep {/^\s*\d+/} (`ps -p $parent_id`))[0];

  my $parent_name = (split /\s+/, $parent, 5)[4];

  print $parent_name;

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On my Linux box it outputs the following: 
  $ ./parent-process.pl
  bash
  $

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Re: Re: Parent process name
by deibyz (Hermit) on May 28, 2004 at 15:08 UTC
    Thanks a lot!

    It works with one little change:

    $ ps -p xxxx

  PID TTY          TIME CMD
29580 pts/4    00:00:00 bash

$ ps -p yyyy

   PID TTY      TIME CMD
  9556 pts/49   0:00 bash

    [download]
    See the blank space? Depending on it presence, I have to take the forth or the fifth elemnt of the last split. It works changing this line:
    my $parent = (grep {/^\s*\d+/} (`ps -p $parent_id`))[0];

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    With this:
    my $parent = " ".(grep {/^\s*\d+/} (`ps -p $parent_id`))[0];

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    Now I have at least one blank and have allways to take fifth element. Thanks again for the code.
    BTW, even if I work with UNIX, I must deal with different flavours (UNIX, Solaris, HP-UX...) and don't know if ps will output the same format everywhere (I'm going to test it).

    And the worst thing, I've just been told to make it run on Window$ 8( Is there anyway to get rid of the ps calls?

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      An easier way to get the parent process ID would be to call the getppid() function.

      $parent_id = getppid();
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      Good catch on the leading space ++

      "And the worst thing, I've just been told to make it run on Window$" Ouch!

      Well there's Win32::Process::Info for MS (which I have not used and know nothing about) and Proc::ProcessTable for unix (which I haven't used yet either), but they might be worth looking at.

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      Here's a windows version:

      use strict;
use Win32::Process::Info;

my $pihandle = Win32::Process::Info->new();
my @procinfo = $pihandle->GetProcInfo();

my $ParentPID;
my %ProcNames;

foreach my $PIDInfo (@procinfo) {
    $ProcNames{$PIDInfo->{ProcessId}} = $PIDInfo->{Name};

    if ($PIDInfo->{ProcessId} == $$) {
        $ParentPID = $PIDInfo->{ParentProcessId};
    }
}

print "Parent's name is ", $ProcNames{$ParentPID}, "\n";

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