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Date: Mon, 10 Jun 1996 20:54:56 GMT
Message-Id: <199606102054.UAA03545@jraynard.demon.co.uk>
From: James Raynard <fqueries@jraynard.demon.co.uk>
To: Eric.Berenguier@sycomore.fr
CC: questions@freebsd.org
In-reply-to: <v01530503ade1e4a001d7@[192.134.92.34]> (message from Eric
	Berenguier on Mon, 10 Jun 1996 16:51:49 +0200)
Subject: Re: Bug in truncate function ?
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> here is a small exemple that doesn't work as i think it should:
> 
> -- Exemple -----------------------------------------------------------
> #include <fcntl.h>
> 
> main() {
>   int fd;
>   fd = open("/tmp/pp01234", O_RDWR | O_CREAT , 0600);
>   if (ftruncate(fd,0)<0) {
>     perror("truncate");
>   }
> }
> ----------------------------------------------------------------------
> 
> this program ouputs:
> truncate: invalid argument

This works fine if you include unistd.h, as recommended by the
ftruncate man page:-

$ cat temp.c
#include <fcntl.h>
#include <unistd.h>

main() {
  int fd;
  fd = open("/tmp/pp01234", O_RDWR | O_CREAT , 0600);
  if (ftruncate(fd,0)<0) {
    perror("truncate");
  }
}
$ gcc temp.c
$ ./a.out
$ ls -l /tmp/pp01234 
-rw-------  1 james  bin  0 Jun 10 20:48 /tmp/pp01234

PS I always compile test programs with -Wall - this would have picked
up the missing header, as well as one or two less important omissions
which are left as an exercise for the reader 8-)

-- 
James Raynard, Edinburgh, Scotland
james@jraynard.demon.co.uk
jraynard@FreeBSD.ORG