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in reply to Re: Re: A Quick fork theory question
in thread A Quick fork theory question

Okay, this may be difficult to follow along to; but I will do my best.

When you fork, your children processes get an exact replica of the process. So, your first child gets spawned. Now, it has a copy of $i which has the value zero. So, it is spawned, it runs the phork() subroutine, and it returns to the for loop with a $i of 0. So, it beings to execute the loop; and your first child process forks its own child and that child (the first child of the first child of the parent) is spawned and it gets a copy of the memory block who has a $i of 1. This stuff happens some more with the second child of the parent and so on. What you want is something along these lines: (warning: untested)
#!/usr/bin/perl -w use strict; my $childLimit = shift @ARGV; #get total number of children my @pids = (); #array of pids of children for(my $i = 0; $i < $childLimit; $i++) { if( !( $pids[$i] = fork() ) ) { # in the child callChildSub(); exit(0); # exit from the child process IMPORTANT } } foreach my $pid (@pids) { waitpid $pid, 0; } sub callChildSub() { print "I am the child with pid $$.\n"; }
Of course, that needs some error-checking and such, but that should get you started.

Jeremy