Article View: comp.std.c
Article #1226Re: Implementation of semaphores in "c"
From: 28-Aug-1992 1129
Date: Fri, 28 Aug 1992 02:33
Date: Fri, 28 Aug 1992 02:33
47 lines
1864 bytes
1864 bytes
NOTICE TO NEW STUDENTS: Newsgroup comp.std.c is for discussions of
standardization issues (e.g. ISO/ANSI C standard, maybe POSIX C standard,
whether various implementations conform, whether various programs are
strictly conforming, etc.).
In article <1992Aug27.114420.20501@cam.compserv.utas.edu.au> kleung@esk.compserv.utas.edu.au (Kam Leung) writes:
>#include <stdio.h>
>#include <sys/types.h>
ISO C doesn't have <sys/types.h>
>#define N 6
>int s[N], me;
>enum status {nthinking,vhungry,neating} ;
>enum status p[N];
>main()
>{
> int i, ;
ISO C doesn't allow an empty declarator (after your comma).
> void PHILOSOPHER(),
> think(), eat(), hungry();
> me = 1; /* initial open state of main semaphore */
> for (i=1;i<N;i++) /*initialise 1-5 philosophers to thinking*/
> { s[i] = 0; p[i] = nthinking;} /* private semaphore s[i]=0,close*/
> for (i=1; i<N; i++){
> if (fork() == 0) PHILOSOPHER(i);
ISO C doesn't have fork().
> }
> ..
> ..
> kill(0,9);
ISO C doesn't have kill().
>}
If the above answers don't help you, then perhaps you need to ask the
tutors for your course. If they can't help you, then perhaps you need
to post in a newsgroup concerning the UNIX operating system, to learn
why separate processes have separate data spaces.
--
Norman Diamond diamond@jit081.enet.dec.com
If this were the company's opinion, I wouldn't be allowed to post it.
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arc1-ca.pugleaf.net!sparky!uunet!wupost!zaphod.mps.ohio-state.edu!pacific.mps.ohio-state.edu!linac!att!ucbvax!jit081.enet.dec.com!diamondShow Full Headers
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Path: arc1-ca.pugleaf.net!sparky!uunet!wupost!zaphod.mps.ohio-state.edu!pacific.mps.ohio-state.edu!linac!att!ucbvax!jit081.enet.dec.com!diamond From: diamond@jit081.enet.dec.com (28-Aug-1992 1129) Newsgroups: comp.std.c Subject: Re: Implementation of semaphores in "c" Message-ID: <9208280233.AA23354@enet-gw.pa.dec.com> Date: 28 Aug 92 02:33:55 GMT Sender: daemon@ucbvax.BERKELEY.EDU Lines: 47