Perl: Waiting for background process to finish.

Question

My problem is that when I run the following it will say that the bash script has finishes successfully. But it doesnt wait for the script to finish, if it quits to early it will move a file that it needs. So what am I doing wrong that it wont wait for the background process to finish to move the files?

my $pid = fork();
    if($pid == -1){
     die;
    } elsif ($pid == 0){
     #system(@autoDeploy) or die;
     logit("Running auto deploy for $bundleApp");
     exec("./deployer -d $domain.$enviro -e $enviro >> /tmp/$domain.$enviro &") 
                    or logit("Couldnt run the script.");
    }
    while (wait () != -1){

    }
    logit("Ran autoDeploy");

    logit("Moving $bundleApp, to $bundleDir/old/$bundleApp.$date.bundle");
    move("$bundleDir/$bundleApp", "$bundleDir/old/$bundleApp.$date.bundle");
    delete $curBundles{$bundleApp};

Answer 1

You don't need to use & in your exec parameters, as you're already running under a fork.

Answer 2

The simplest thing that you're doing wrong is using & at the end of the exec commandline -- that means you're forking twice, and the process that you're waiting on will exit immediately.

I don't actually see what purpose fork/exec are serving you at all here, though, if you're not redirecting I/O and not doing anything but wait for the exec'd process to finish; that's what system is for.

system("./deployer -d $domain.$enviro -e $enviro >> /tmp/$domain.$enviro") 
                and logit("Problem running deployer: $?");

will easily serve to replace the first twelve lines of your code.

And just as a note in passing, fork doesn't return -1 on failure; it returns undef, so that whole check is entirely bogus.