Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!convex!usenet
From: tchrist@convex.COM (Tom Christiansen)
Newsgroups: comp.lang.perl
Subject: Re: Scanning "ps" output with Perl
Message-ID: <1991May03.184755.16450@convex.com>
Date: 3 May 91 18:47:55 GMT
References: <1991May3.162019.5613@uvaarpa.Virginia.EDU>
Sender: usenet@convex.com (news access account)
Reply-To: tchrist@convex.COM (Tom Christiansen)
Organization: CONVEX Software Development, Richardson, TX
Lines: 26
Nntp-Posting-Host: pixel.convex.com

From the keyboard of ted@evi.com (Ted Stefanik):
:I've noticed that several Perl utilities scan "ps" output using splits
:and/or regular expressions.  I'd like to add some cautions to these
:approaches.
:
:When a particular process's statistics numbers get too big for the column space
:alloted to that number, ps just slams the number into the preceeding column.


This is unfortunately pretty OS dependent.  Some versions (mine, for
example) seems to guarantee a space between fields, even if some fields
should get wide.

    USER       PID %CPU %MEM   SZ  RSS TT  STAT   TIME COMMAND
    tchrist    550 53.1  0.1 6508  464 o2  R      0:01 ps axu
    user0    29596  0.0 12.6 65568 64300 q1  T N   10:34 program
    user1    22172 52.4 31.2 278648 78840 pc VR N   100:14 another_program

The only thing here mildly difficult is finding all the STAT stuff, which
can contains blanks.


--tom
--
Tom Christiansen		tchrist@convex.com	convex!tchrist
		"So much mail, so little time."