Using the open() system call

Question

I\'m writing a program that writes output to a file. If this file doesn\'t exist, I want to create it.

Currently, I\'m using the following flags when calling open: O

Answer 1

Just use the optional third argument to open:

int open(const char* pathname, int flags, mode_t mode);

so like this:

open("blahblah", O_CREAT | O_WRONLY, S_IRUSR | S_IWUSER | S_IRGRP | S_IROTH);

See man open(2).