Sorry to revive this, but I have a problem with the way my code is working and it is related to this issue.

I am using the same if...fork...else...exec process as @davorg but when I look at the ps -ef output I find 2 processes.

if(my $pid = fork()){
    $this->set_pid_in_db($id, $pid);
}
# Child process starts service and inherits child PID
else{
    my $command = sprintf("%s %s 1>>%s 2>>%s", $this->fnClient(), $id,
+ $this->fnOe($id), $this->fnOe($id));
    #my $command = sprintf("%s %s", $this->fnClient(), $id);
    exec($command);
}

>ps -ef | grep SB
mark 11970     1  0 07:57 pts/1    00:00:00 sh -c /code/SBClient2.pl j
+ob1 1>>/log/log.1.oe 2>>/log/log.1.oe
mark 11971 11970 77 07:57 pts/1    00:00:06 /usr/bin/perl /code/SBClie
+nt2.pl job1

[download]

And the PID that was set on line 2 is 11970 rather than 11971. Of course, I can still test to see if 11970 is running and that will tell me if 11971 is running. And I can kill 11970 and that will kill 11971.

However, what confuses me is that if I don't redirect output and error to a file (i.e. use the commented out command instead), then 1 process rather than 2 processes are started.

Does anyone know why this happens?

In reply to Re: getting a child's process ID by markdibley
in thread getting a child's process ID by Seshouan

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