/* * Locking routines for System V. */ #include my_lock(fd) int fd; { lseek(fd, 0L, 0); /* rewind before lockf */ if (lockf(fd, F_LOCK, 0L) == -1) /* 0L -> lock entire file */ err_sys("can't F_LOCK"); } my_unlock(fd) int fd; { lseek(fd, 0L, 0); if (lockf(fd, F_ULOCK, 0L) == -1) err_sys("can't F_ULOCK"); }