Controlling processes knowing the PID's

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1

Dear all,
suppose that I start a process (named "father"). "father" starts in turns a process called "child" with an execv call (after a fork). In this way "father" will be notified if "chlid" crashes (SIGCHILD mechanism). The problem is:
if "father" crashes, how can I do to be recreate a mechanism like that of SIGCHILD when I restart a process that will substitute "father", say "father1"?

Anyway, I have previously stored the PID of the "child" process.

I was trying to change the PPID of "child", but it seems it doesn't work.

Could you help me?

2

Depending on the version of unix that you are using, you may have a ptrace() system call that is really intended only for debuggers. You may be able to use this to attach to a process and arrange for notification of when it exits. I really would urge you to avoid that path. ptrace() is not portable and there may be performance consequences of using it.

Other than the ugly ptrace() solution, I know of no other way to do this. The most reasonable thing to do is to fix "father" so that it no longer crashes.