No, Remember fork creates a copy of the parent's environment in the child's process, so whenever you change the child's variable, it won't have any effect on the parent's and vice versa.
One idea is to increase the child counter in the parent process and decrement in the SIGCHLD handler which will get invoked when the child process exits. Please refer to the Camel book by Larry Wall or Perlipc manpage, it contains information about how to do it. Hint. Look for "Reaper". If you are running latest Perl version, you should consider threading instead of fork. It is platform independent, light-weight and easy to pass information back and forth. Please refer to perlthrtut for more information. Hth, with warm regards, Venkat Saranathan Gulf Breeze Software www.gulfsoft.com GulfBreeze Blog www.gulfsoft.com/blog -----Original Message----- From: Travis Thornhill [mailto:[EMAIL PROTECTED] Sent: Friday, July 21, 2006 11:47 PM To: beginners@perl.org Subject: fork question I thought I understood this but maybe I don't. When perl forks it creates an exact copy of itself with open files, same variables, hashes, arrays, etc. But when a variable in one changes, do they all change? What's wrong with how I'm trying to use the $children variable to track whether or not I still have processes running? #!/usr/local/bin/perl use strict; use warnings; my $pid; my $children = 0; my @args = ( "arg1", "arg2", "arg3", "arg4", ); foreach my $arg ( @args ) { if ( $pid = fork() ) { #parent #do nothing yet } else { #child $children++; system("my_command -a $arg"); $children--; exit; } } # end foreach # didn't let children fall through, so this is in the parent process # this is where I do lots of stuff waiting for $children to equal zero while ( $children ) { # gather some data from "ps" and parsing log files, etc... } #end of script Thanks in advance for any insights, Travis. --------------------------------- Do you Yahoo!? Next-gen email? Have it all with the all-new Yahoo! Mail Beta. -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] <http://learn.perl.org/> <http://learn.perl.org/first-response>
