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From: eric@ee.ualberta.ca (Eric Norum)
Newsgroups: comp.sys.next
Subject: Yet another bug in the NextStep 2.0 C library.
Keywords: strtod
Message-ID: <1991Apr6.212435.4876@ee.ualberta.ca>
Date: 6 Apr 91 21:24:35 GMT
Sender: news@ee.ualberta.ca
Reply-To: eric@ee.ualberta.ca (Eric Norum)
Organization: University of Alberta Electrical Engineering
Lines: 32

Consider the following program fragment:

#include <stdlib.h>
#include <stdio.h>
	.
	.
	char *cp, *ptr;
	double x;
	.
	.
	cp = "trash"
	x = strtod(cp, &ptr);

From the description of strtod:
          If the value of ptr is not (char **)NULL, the variable to
          which it points is set to point at the character after the
          last number, if any, that was recognized.  If no number can
          be formed, *ptr is set to str, and zero is returned.

The strtod supplied with NextStep 2.0 does not behave as expected.
It returns a zero and `ptr' is set to point at the '\0' at the end
of the `trash' string indicating a valid number was converted.

This is most annoying.  I use strtod instead of atof because strtod
is supposed to return an indication of invalid data.  Has anyone got
a fix for this?

-- 
Eric Norum
Dept. of Electrical Engineering      eric@ee.ualberta.ca
University of Alberta
Edmonton, Canada.                   phone: (403) 492-4626