Next: Process Control and Management Up: File and Directory Manipulation Previous: File Manipulation Routines . ... extern int errno; . It can be manually reset within a C program other wise it simply retains its last value. int chmod(char *path, int mode) change the mode of access of a file. specified by path to the given mode . ... Leftmost bit = read access (on/off) middle is write, right is executable. ... int stat(char *path, struct stat *buf), int fstat(int fd, struct stat *buf) . ...