NetNews Offline 2/NetNews Offline Volume 2.iso/news/comp/lang/c-part1/3027

Internet Message Format | 1996-08-05 | 1.6 KB

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From: Lawrence Kirby <[e-mail]>
Newsgroups: comp.lang.c
Subject: Re: i = atoi(NULL);
Date: Thu, 25 Jan 96 14:15:57 GMT
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In article <[e-mail]>
           [e-mail] "Shimon Cohen" writes:

>Thats right !
>I called  atoi like this:
>i = atoi (strtok (input_str, ",");
>My compiler (BC4.0) docs says:  "If no conversion could be performed,
>zero is returned." . I used this fact and it works fine. but not under
>the unix machine of my teacher :-(

This hinges on what is meant by "If no conversion could be performed".
What it actually means is if the contents of the string passed to
atoi() is not recognised as a number e.g. atoi("A1234") would return 0. You
are still required to pass atoi() a pointer to a valid string, a null
pointer doesn't qualify. Your system probably accepts it because it
doesn't support the hardware protection required to trap an invalid
null pointer dereference whereas the Unix system does.

Thank the Unix system - it helped you to identify and correct a bug in your
program.

--
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Lawrence Kirby | [e-mail]
Wilts, England | [e-mail]
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