SHUTDOWN(2) BSD System Calls Manual SHUTDOWN(2)
shutdown -- shut down part of a full-duplex connection
shutdown(int s, int how);
The shutdown() call causes all or part of a full-duplex connection on the
socket associated with s to be shut down. If how is 0, further receives
will be disallowed. If how is 1, further sends will be disallowed. If
how is 2, further sends and receives will be disallowed.
A 0 is returned if the call succeeds, -1 if it fails.
The call succeeds unless:
[EBADF] S is not a valid descriptor.
[ENOTSOCK] S is a file, not a socket.
[ENOTCONN] The specified socket is not connected.
The shutdown() function call appeared in 4.2BSD.
4.2 Berkeley Distribution June 4, 1993 4.2 Berkeley Distribution