Re: CLONE_PID (was: POSIX.1b semaphores)

Matthew S. Crocker (
20 Nov 1996 14:44:57 GMT

Linus Torvalds ( wrote:

: The other possibility I see is to always think of the "high bits zero"
: process as the parent process to all threads (it is), and not special-case
: the zero at all. If you send a signal with high bits zero, it goes to the
: "parent", and nobody else.

I think this is the 'correct' way. Send the signal to the parent.
Let the parent decide if it wants to pass the signal on to all the
children. You can even add a C library API that will send a signal to
all the children. The kernel would still maintain the linked list for
thread parent/children (brothers/sisters) for the API to use when
propogating the signal down the chain.

By doing it this way you can easily maintain POSIX requirements using
the API. We all know how you like to keep everything out of the
kernel which doesn't really belong there.

The kernel should be able to:

create/destroy a thread
send a signal to any thread/process

let the application handle the 'walk the process/thread list' stuff

: PS. Oh, and while I'm orating here, I might as well tell everybody that
: I've been busy writing my masters thesis, and as a result I've moved all
: the mailing lists to a low-priority channel. I'll try to concentrate on my
: thesis for a while, so I'll be less active than usual. Don't worry, this
: is all temporary.

Geez, you would think the kernel would count as a thesis ;)

BTW, is 2.0.25 the FINAL 2.0 kernel our are there more fixes in the


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