Re: Async IO

Tim Wright (
Wed, 05 Feb 1997 11:06:26 PST

In message <>,
Michael Eyrich writes:
> Negativ signal values are used to reach a process with all its childs
> i.e. a process group. Positiv signal values are used to reach exactly
> one process and the 0-signal is used to check if there is a process with
> this number ..

No, negative *pids* are used to signal a process group. (pid_t) -1
signals all processes whose real uid matches the effective uid of the
sender. I'm not sure what Posix has to say about the valid range of
signals, but I suspect it is probably limited.


Tim Wright, Worldwide Technical Services,         |  Email:
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