Path: utzoo!utgpu!cunews!bcars8!bnrgate!bigsur!bnr-rsc!hounsell
From: hounsell@chekov.UU.NET (Rob Hounsell)
Newsgroups: comp.sys.hp
Subject: Xtank port and jmp_buf puzzle
Keywords: xtank jmp_buf
Message-ID: <3160@bnr-rsc.UUCP>
Date: 1 Jun 90 15:08:59 GMT
Sender: news@bnr-rsc.UUCP
Reply-To: uunet!chekov!hounsell
Organization: Northern Telecom, Ottawa, Canada
Lines: 37

Folks,

  I may be doing this the hard way, but.....

  A friend sent me the source for xtank a while back. Unfortunately, it had no
HPUX port in it, so off I went to port it myself. Things seem fine, EXCEPT for
a section in thread.c (which controls the robot tanks) like so:

    /* Modify current state's stack pointer in jmp_buf state */
    bufend = (unsigned int)buf + bufsize - 1 - sizeof(thd->state);

    /* Set stack pointer in jmp_buf to bufend.
     * This is extremely machine and OS dependent.
     * Often you can find out what register of the jmp_buf has the
     * stack pointer by looking in /usr/include/setjmp.h on your machine.
     */
#ifdef vax  /* Vaxen */
    bufend -= sizeof(Thread);
    thd->state[0] = bufend;
#endif
#if	(defined(ibm032) || defined(ibm370)) /* IBM RT */
    thd->state[0] = bufend;
#endif
 etc.....

  The setjump.h for HPUX 6.5 running on HP300 series workstations does NOT give
a clue what register to use, or how to set bufend. Can anyone suggest the
correct values??

Rob
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|  Rob Hounsell                      |                                        |
|  UUNET:  ...!chekov!mcrae!hounsell |  "You guys start coding, and I'll go   |
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