shutdown(2)		       System Calls Manual		     shutdown(2)

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

LIBRARY
     Standard C library (libc, -lc)

SYNOPSIS
     #include <sys/socket.h>

     int shutdown(int sockfd, int how);

DESCRIPTION
     The  shutdown()  call causes all or part of a full-duplex connection on the
     socket associated with sockfd to be shut down.  If how is SHUT_RD,	 further
     receptions	 will  be  disallowed.	If how is SHUT_WR, further transmissions
     will be disallowed.  If how is SHUT_RDWR, further receptions and  transmis-
     sions will be disallowed.

RETURN VALUE
     On	 success,  zero is returned.  On error, -1 is returned, and errno is set
     to indicate the error.

ERRORS
     EBADF  sockfd is not a valid file descriptor.

     EINVAL
	    An invalid value was specified in how (but see BUGS).

     ENOTCONN
	    The specified socket is not connected.

     ENOTSOCK
	    The file descriptor sockfd does not refer to a socket.

STANDARDS
     POSIX.1-2024.

HISTORY
     POSIX.1-2001, 4.4BSD (first appeared in 4.2BSD).

NOTES
     The constants SHUT_RD, SHUT_WR, SHUT_RDWR have the value 0, 1,  2,	 respec-
     tively, and are defined in <sys/socket.h> since glibc-2.1.91.

BUGS
     Checks for the validity of how are done in domain-specific code, and before
     Linux  3.7	 not all domains performed these checks.  Most notably, UNIX do-
     main sockets simply ignored invalid values.  This	problem	 was  fixed  for
     UNIX domain sockets in Linux 3.7.

SEE ALSO
     close(2), connect(2), socket(2), socket(7)

Linux man-pages 6.18		   2025-10-29			     shutdown(2)