Fork creates and runs a new instance of your program, just like if you ran it, except that the second program is a carbon copy of the first, at the point the fork occurs.

The program forks at the $pid=fork and suddenly there are two programs running, both doing the next statement (the if). The only difference is that one will have $pid = 0 and one will have $pid = 1234 or some number, being the pid of the child. 

my $pid;
$pid = fork;
 if ( $pid ) {
  #We are the parent
  print "Successfully forked, I am the parent\n";
 } 
 else {
   if ( $pid == 0 ) {
   #We are the child
   print "Successfully forked, I am the child\n";
   
  }
  else {
   #undef value - no fork happened
   print "Fork failed for some strange reason\n";
   
  } 
 }

[download]

I'm currently writing a module to do this and handle IPC as well. If you can hold on a few days I'll clean up the module and post it.

____________________
Jeremy
I didn't believe in evil until I dated it.

In reply to Re: Forked off! by jepri
in thread Forked off! by larryk

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.