Apple - Linux' `ps f` (tree view) equivalent on OSX?

You can install the pstree command using either Homebrew (my personal favourite), MacPorts or Fink and you'll get a command-line, tree view of processes on your Mac.

With Homebrew installed, just run:

brew install pstree

then use it like pstree from the command line.

The below small perl script I've called 'treeps' that should do exactly that; works on linux (Sci Linux 6) + OSX (10.6, 10.9)

Example output:

$ ./treeps
    |_ 1        /sbin/launchd
        |_ 10       /usr/libexec/kextd
        |_ 11       /usr/sbin/DirectoryService
        |_ 12       /usr/sbin/notifyd
        |_ 118      /usr/sbin/coreaudiod
        |_ 123      /sbin/launchd
    [..]
           |_ 157      /Library/Printers/hp/hpio/HP Device [..]
           |_ 172      /Applications/Utilities/Terminal.app [..]
              |_ 174      login -pf acct
                 |_ 175      -tcsh
                    |_ 38571    su - erco
                       |_ 38574    -tcsh

Here's the code..

#!/usr/bin/perl
# treeps -- show ps(1) as process hierarchy -- v1.0 [email protected] 07/08/14
my %p; # Global array of pid info
sub PrintLineage($$) {    # Print proc lineage
  my ($pid, $indent) = @_;
  printf("%s |_ %-8d %s\n", $indent, $pid, $p{$pid}{cmd}); # print
  foreach my $kpid (sort {$a<=>$b} @{ $p{$pid}{kids} } ) {  # loop thru kids
    PrintLineage($kpid, "   $indent");                       # Recurse into kids
  }
}
# MAIN
open(FD, "ps axo ppid,pid,command|");
while ( <FD> ) { # Read lines of output
  my ($ppid,$pid,$cmd) = ( $_ =~ m/(\S+)\s+(\S+)\s(.*)/ );  # parse ps(1) lines
  $p{$pid}{cmd} = $cmd;
  # $p{$pid}{kids} = (); <- this line is not needed and can cause incorrect output
  push(@{ $p{$ppid}{kids} }, $pid); # Add our pid to parent's kid
}
PrintLineage(($ARGV[0]) ? $ARGV[0] : 1, "");     # recurse to print lineage starting with specified PID or PID 1.

I adapted Greg Ercolano's perl script to python script.

#!/usr/bin/env python2.7

import subprocess as subp
import os.path
import sys
import re
from collections import defaultdict

def psaxo():
    cmd = ['ps', 'axo', 'ppid,pid,comm']
    proc = subp.Popen(cmd, stdout=subp.PIPE)
    proc.stdout.readline()
    for line in proc.stdout:
        yield line.rstrip().split(None,2)

def hieraPrint(pidpool, pid, prefix=''):
    if os.path.exists(pidpool[pid]['cmd']):
        pname = os.path.basename(pidpool[pid]['cmd'])
    else:
        pname = pidpool[pid]['cmd']
    ppid = pidpool[pid]['ppid']
    pppid = pidpool[ppid]['ppid']
    try:
        if pidpool[pppid]['children'][-1] == ppid:
            prefix = re.sub(r'^(\s+\|.+)[\|`](\s+\|- )$', '\g<1> \g<2>', prefix)
    except IndexError:
        pass
    try:
        if pidpool[ppid]['children'][-1] == pid:
            prefix = re.sub(r'\|- $', '`- ', prefix)
    except IndexError:
        pass
    sys.stdout.write('{0}{1}({2}){3}'.format(prefix,pname,pid, os.linesep))
    if len(pidpool[pid]['children']):
        prefix = prefix.replace('-', ' ')
        for idx,spid in enumerate(pidpool[pid]['children']):
            hieraPrint(pidpool, spid, prefix+' |- ')

if __name__ == '__main__':
    pidpool = defaultdict(lambda:{"cmd":"", "children":[], 'ppid':None})
    for ppid,pid,command in psaxo():
        ppid = int(ppid)
        pid  = int(pid)
        pidpool[pid]["cmd"] = command
        pidpool[pid]['ppid'] = ppid
        pidpool[ppid]['children'].append(pid)

    hieraPrint(pidpool, 1, '')

Example output:

launchd(1)
 |- syslogd(38)
 |- UserEventAgent(39)
 |- kextd(41)
 |- fseventsd(42)
 |- thermald(44)
 |- appleeventsd(46)
...
 |- iTerm(2879)
 |   |- login(2883)
 |   |   `- -bash(2884)
 |   |       `- Python(17781)
 |   |           `- ps(17782)
 |   |- login(7091)
 |   |   `- -bash(7092)
 |   |       `- ssh(7107)
 |   `- login(7448)
 |       `- -bash(7449)
 |           `- bash(9040)
 |               `- python(9041)
 |- installd(2909)
 |- DataDetectorsDynamicData(3867)
 |- netbiosd(3990)
 |- firefox(5026)
...