shutdown -- shut down part of a full-duplex connection
Standard C Library (libc, -lc)
shutdown(int s, int how);
The shutdown() system call causes all or part of a full-duplex connection
on the socket associated with the file descriptor s to be shut down. The
how argument specifies the type of shutdown. Possible values are:
SHUT_RD further receives will be disallowed.
SHUT_WR further sends will be disallowed.
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
The shutdown() system call fails if:
[EBADF] The s argument is not a valid file descriptor.
[EINVAL] The how argument is invalid.
[ENOTCONN] The socket is not connected.
[ENOTSOCK] The s argument does not refer to a socket.
The shutdown() system call is expected to comply with IEEE Std
1003.1g-2000 (``POSIX.1''), when finalized.
The shutdown() system call appeared in 4.2BSD. The SHUT_RD, SHUT_WR, and
SHUT_RDWR constants appeared in IEEE Std 1003.1g-2000 (``POSIX.1'').
FreeBSD 5.2.1 February 27, 2001 FreeBSD 5.2.1 [ Back ]