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Date: Mon, 21 Jul 2003 11:42:06 -0600
From: Chad David <davidc@issci.ca>
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Subject: Re: Correct way to call execve?
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On Mon, Jul 21, 2003 at 01:23:21PM -0400, Leo Bicknell wrote:
> In a message written on Mon, Jul 21, 2003 at 11:15:38AM -0600, Chad David wrote:
> > Try cc -Wwrite-strings -Wcast-qual exec.c.
> > 
> > You cannot simply cast away a const.
> 
> Grumble, will someone give me all the warnings you want turned on so I
> can work around all of them? :)
> 
> % cat exec.c
> 
> #include <unistd.h>
> #include <paths.h>
> #include <string.h>
> 
> int main(int argc, char *const argv[], char *const envp[]) {
>   char *const execargv[] = { strdup(_PATH_BSHELL), strdup(NULL) };
> 
>   execve(_PATH_BSHELL,execargv,envp);
> 
>   return 0;
> }
> % cc -Wwrite-strings -Wcast-qual exec.c
> % cc -Wall exec.c

You can/should probably skip the strdup(NULL), or ensure V in malloc.conf :).

I assumed it was obvious that you could copy the data, but I believe
the intent of the original question was to find an alternative.  As
far as I know there isn't one.  A const is a const, except in C++.

-- 
Chad David        davidc@issci.ca
www.FreeBSD.org   davidc@freebsd.org
ISSci Inc.        Calgary, Alberta Canada