There is no foreground process. It's using setsid() to disassociate the child from the parent, then the parent exits. The remaining process (the child) forks a process it's the parent of and they both do their own thing.

I should have just left out the setsid() because you're apparently confused by what I intended to do with it. I wasn't sure if it was pretinent or not, so I mentioned it.

I'm doing something like this:

use POSIX qw/setsid/;

if ( fork() ) {
    exit;
} else {
    setsid();
}
# now the foreground process is gone and I'm the child
if ( fork() ) {
    &do_something();
} else {
    &do_something_else();
}
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They both stay around in an infinite loop doing whatever they're supposed to do. I have to kill them both or whichever one I don't kill sticks around. Like from ps auxf:

iniquity 26464  0.5 15.9  2976  2348  ?  S   21:41   0:00 perl -w ./si
+ncd.pl 
iniquity 26465  0.0 15.4  2920  2276  ?  S   21:41   0:00  \_ perl -w 
+./sincd.p
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If I kill 26464, 26465 doesn't go away.

local $_ = "0A72656B636148206C72655020726568746F6E41207473754A";
while(s/..$//) { print chr(hex($&)) }
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