fcntl

This module performs file control and I/O control on file descriptors. It is an interface to the fcntl() and ioctl() Unix routines. File descriptors can be obtained with the fileno() method of a file or socket object.

Functions

fcntl(fd, op, [arg])	Perform the operation op on file descriptor fd.
flock(fd, operation)	Perform the lock operation op on file descriptor fd.
ioctl(fd, op[, arg[, mutate_flag]])	Perform the operation op on file descriptor fd.
lockf(fd, operation[, length, start, whence])	This is essentially a wrapper around the fcntl() locking calls.