Messages in this thread |  | | | Date | Thu, 14 Aug 1997 16:27:36 +0200 (MET DST) | | From | Andries.Brouwer@cwi ... | | Subject | Re: Killing clones |
| |
Linus Torvalds:
: On Thu, 14 Aug 1997, Albert D. Cahalan wrote: :: :: To make threaded apps very compatible: :: getpid() could return just the bottom 16 bits to make userspace :: even more happy. Then a gettid() function gets the whole 32 bits. :: Normal kill() handles both just fine.
: Works for me.
:: Symmetry requires numbering unthreaded processes from 0x10000. :: They still show up with low numbers and can be killed with the :: low numbers. :: That gets rid of some special case code for thread #1.
: Sure, I can live with this (in fact I think I prefer it to my original : setup).
I have one comment: Several Linux applications have security holes caused by the fact that a pid has only 16 bits (so that one can trick some suid process into sending a signal to some other privileged process by spawning 32000 processes). Because of such and other reasons it might be a good idea to move to a 32-bit pid in the future, so that pid's will be unique for a process.
This again might mean that the outside world must know as little as possible about the structure of a tid.
Andries
|  |