fsetxattr() fails on a writable descriptor?

[Pádraig Brady]

fsetxattr() is failing for me when the permissions are readonly
but the descriptor is writable as demonstrated by the program below.
I've tried this on ext3 and ext4 with libattr-2.4.43-3.fc11.i586
and linux-2.6.30.5-43.fc11.i586

Is this expected?

cheers,
Pádraig.

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <attr/libattr.h>
#include <stdio.h>
#include <unistd.h>

int main(void)
{
    int wfd;
    if ((wfd=open("writable", O_CREAT|O_WRONLY|O_EXCL, S_IRUSR)) == -1)
        fprintf(stderr, "open('writable') error [%m]\n");
    if (write(wfd, "data", 1) == -1)
        fprintf(stderr, "write() error [%m]\n");
    if (fsetxattr(wfd, "user.test", "test", 4, 0) == -1)
        fprintf(stderr, "fsetxattr() error [%m]\n");
}