I have the following data (output from "ps -eo pid,ppid,comm"): 
 PID  PPID  COMMAND
   0     0  sched
   1     0  /sbin/init
   7     0  vmtasks
 105     1  /usr/lib/saf/sac
7184     1  /usr/bin/java
7222     1  /usr/lib/utmpd
7501  6223  /usr/sbin/nscd
7507  7184  /bin/sh
7508  7507  /usr/bin/perl
7510  5044  /usr/bin/grep
7512  4333  /usr/bin/egrep
7515  7508  sh
7516  7515  <defunct>

[download]

and I'm trying to write a script that will output a "trace" of a defunct process, so to speak. It would output something like this:

   1     0  /sbin/init
7184     1  /usr/bin/java
7507  7184  /bin/sh
7508  7507  /usr/bin/perl
7515  7508  sh
7516  7515  <defunct>

[download]

I'm having trouble deciding what to use to store this data. I'm thinking a hash, but I need to keep track of three different values. Would a multi-dimensional hash work in this case? I've been reading about multi-dimensional hashes, but I'm still unsure if I should be using them here. The output of the ps command is stored in a file and the file is large, so I would need an efficient script. Thanks for any suggestions.

In reply to Help parsing this data by cspctec

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