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From: ben <brouits@free.fr>
To: linux-c-programming@vger.kernel.org
Subject: Re: strtok, bus error
Date: Tue, 17 Feb 2009 05:04:22 +0100	[thread overview]
Message-ID: <499A3746.1070502@free.fr> (raw)
In-Reply-To: <125035.76273.qm@web63404.mail.re1.yahoo.com>

Fundu a écrit :
> i'm trying to do pretty simple replacement using strtok.
> but it looks like i have missed some subtle difference between the two following 
>   
>   char src[]  = "hello world #";
>   char *other = "hello world #";

i don't know if it is a compiler feature (storage behavior into the DATA
segment), or a linux kernel feature, or if it is specified in ANSI, but
the second way leads to pointing to a _constant_ string. If someone can
enlighten...

> because if i use "char * other" with strtok it fails with bus error but i use src it works, don't understand what's the difference.
> any insight would be appreciated, TIA!
strtok manpage says it has to _write_ into the string pointed to by its
first parameter. this is not allowed if the pointer points to a constant
string.

then,
you have to point into a string that have been created at runtime.

char* src;
src = malloc (12);
strncpy (src, "hello#world", 11);
...
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  parent reply	other threads:[~2009-02-17  4:04 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-02-17  2:52 strtok, bus error Fundu
2009-02-17  3:57 ` Bryan Christ
2009-02-17  6:31   ` Fundu
2009-02-17  4:04 ` ben [this message]
2009-02-17 20:15   ` Glynn Clements
2009-02-17 21:05     ` ben

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