entropy has asked for the wisdom of the Perl Monks concerning the following question:

My goal is to change the process' name. According to the FAQ, I should just assign to the special $0 variable. This works a little, but the program's name now has four or five lines of spaces after it (when doing a 'ps axww'). Sometimes it works good, sometimes it doesn't. In fact, it seems that long values work, whereas shorter values have the spaces appended.
  • Comment on How do I change my program's name under ps? ($0='abc' is messed up)

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Re: How do I change my program's name under ps? ($0='abc' is messed up)
by rpc (Monk) on May 25, 2001 at 04:37 UTC
    This is because when the process is created, the first argument is allocated to be the size of the actual process name. Try appending a \0 to your fake process name.
[reply]
      \0 doesn't help on linux... On FreeBSD it seems to work with or without the \0 (in addition to displaying the original process name).

      If the memory is pre-allocated, then do I have to worry about overflowing it?

[reply]
        Nope, you don't have to worry about overflowing it in Perl. You do however, when dealing with argv[0] in C, etc.
[reply]

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