On Tuesday, November 13, 2001, at 06:29 , Kevin Bohan wrote: Hi, I have a BSD question and I apologise if this is not the right list, as this is not really my area. However I have a daemon that writes its PID to an external file when it starts up and I have a script that looks for this file, extracts the PID in order to provide a commandline interface that allows the process to be killed. However, when I call getpid to write the PID to the text file it always seems to write a value that is 1 less than the PID shown when I use ps to view the process in question. Also if I call kill on the value returned by getpid it tells me that the process doesn't exist. It would seem that ps is right an getpid is wrong. I can obviously just add one to the value returned by getpid, but is this safe/future-proof? Is this a known issue? What should I do? 'getpid()' is not likely to be wrong, so the smart money would bet that there's a "bug" in your code somewhere. At a guess, what is happening is that you call getpid() early in the process's existance, and that sometime after that, your code does a 'fork', with the parent (which is the process that called 'getpid()') exiting. Then the child continues on as the daemon (it's pid is different than the result of the earlier 'getpid()'). This is fairly standard for daemons, and is, in fact, what the daemon(3) call does. Regards, Justin PS: this is definitely the correct list. --- Justin C. Walker, Curmudgeon-At-Large * Institute for General Semantics | When LuteFisk is outlawed | Only outlaws will have | LuteFisk *--------------------------------------*-------------------------------*