What do you mean by 'chokes', hangs, segfaults, etc? And some of the stuff(lots of it apparently, including what 'caller' happens to be) may be relevant to why it's 'choking'.

Also this bit I think is incorrect on its face: 

if ($pid[$i]=fork()) {   # parent process
    waitpid($pid[$i], 0);  # wait for child
    close ($wh);
    ...

[download]
After each fork, the parent process is going to wait for the most recently forked child to complete BEFORE the next one is forked. All of your forked processes are going to run SERIALLY not in parallel.

What I think you might want to try is this: 

##
## launch children
##
for( $i = 0 ; $i < NUMPROCS ; $i++ ) {
  $pid[$i] = fork() ;
  next if( $pid[$i] != 0 ) ; # fork next process
  ##
  ## child stuff
  ##
  exit(0) ; # when finished
}
##
## gather children
##
foreach( @pid ) {
   waitpid($_, 0) ; # waits for each child
   if( $? != SOMETHINGGOOD ) {
      # bad exit status
   }
}

[download]

In reply to Re: Concurrent Processes by ptkdb
in thread Concurrent Processes by mcogan1966

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.