From: Richard Henderson <rth@cygnus.com>
To: "Kaveh R. Ghazi" <ghazi@caip.rutgers.edu>
Cc: rth@cygnus.com, egcs@cygnus.com
Subject: Re: Is there a HOST_BITS_PER_POINTER macro?
Date: Tue, 10 Feb 1998 03:34:00 -0000 [thread overview]
Message-ID: <19980206111407.32563@dot.cygnus.com> (raw)
In-Reply-To: <199802061648.LAA11516@caip.rutgers.edu>
On Fri, Feb 06, 1998 at 11:48:08AM -0500, Kaveh R. Ghazi wrote:
> > sprintf(foo, "%p", ptr)
> > exit (strcmp(foo, "0"));
The problem is that it is implementation defined what
format pointers are represented in. So you might easily
get any of
0
00000000
0x0
0x00000000
0000:0000
I can think of two possible solutions:
char buf[64];
sprintf (buf, "%p", buf);
#ifdef HAVE_INDEX
exit (index (buf, 'p') == NULL);
#else
exit (strchr (buf, 'p') == NULL);
#endif
since it seems unlikely that any representation will result in 'p',
though of course that's not the only failure mode, or
char buf[64];
char *p = buf, *q = NULL;
sprintf(buf, "%p", p);
sscanf(buf, "%p", &q);
exit (p != q);
if sscanf can be trusted to read them back in. I would think that's
required, but...
r~
next prev parent reply other threads:[~1998-02-10 3:34 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
1998-02-06 8:48 Kaveh R. Ghazi
1998-02-10 3:34 ` Richard Henderson [this message]
-- strict thread matches above, loose matches on Subject: below --
1998-02-07 13:09 Kaveh R. Ghazi
1998-02-07 13:29 ` Richard Henderson
1998-02-05 16:45 Kaveh R. Ghazi
1998-02-05 22:09 ` Joern Rennecke
1998-02-05 22:09 ` Richard Henderson
1998-02-06 0:57 ` Jeffrey A Law
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