fd = open("MYFILE",O_CREAT,S_IWUSR|S_IWGRP|S_IWOTH);

i m opening and creating a file using c program , at the time of open i m giving the permission to the file write for all user (user,group,other) but its not working ,
even cmd [chmod +w MYFILE ] is'n working ..
can you tell me why ??
code:
#include<stdio.h>
#include<fcntl.h>
#include<sys/stat.h>
#include <sys/types.h>
int main()
{
        int fd;fd;
        fd = open("MYFILE",O_CREAT,S_IWUSR|S_IWGRP|S_IWOTH);
        close(fd);
}
not working for group and others.