shutdown(2) BSD System Calls Manual shutdown(2)
shutdown -- shut down part of a full-duplex connection
#include <sys/socket.h> int shutdown(int socket, int how);
The shutdown() call causes all or part of a full-duplex connection on the socket associated with socket to be shut down. If how is SHUT_RD, fur- ther receives will be disallowed. If how is SHUT_WR, further sends will be disallowed. If how is SHUT_RDWR, further sends and receives will be disallowed.
The shutdown() function returns the value 0 if successful; otherwise the value -1 is returned and the global variable errno is set to indicate the error.
The call succeeds unless: [EBADF] Socket is not a valid descriptor. [EINVAL] The how argument is invalid. [ENOTCONN] The specified socket is not connected. [ENOTSOCK] Socket is a file, not a socket.
The shutdown() function call appeared in 4.2BSD. 4.2 Berkeley Distribution March 18, 2015 4.2 Berkeley Distribution
Mac OS X 10.11.6 - Generated Fri Feb 3 08:22:38 CST 2017