osx man page for shutdown

SHUTDOWN(2)						      BSD System Calls Manual						       SHUTDOWN(2)

NAME
     shutdown -- shut down part of a full-duplex connection

SYNOPSIS
     #include <sys/socket.h>

     int
     shutdown(int socket, int how);

DESCRIPTION
     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,
     further 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.

RETURN VALUES
     The shutdown() function returns the value 0 if successful; otherwise the value -1 is returned and the global variable errno is set to indi-
     cate the error.

ERRORS
     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.

SEE ALSO
     connect(2), socket(2)

HISTORY
     The shutdown() function call appeared in 4.2BSD.

4.2 Berkeley Distribution					   June 4, 1993 					 4.2 Berkeley Distribution