shutdown - shut down part of a full-duplex connection


   #include <sys/socket.h>

   int shutdown(int sockfd, int how);


   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 transmissions will be disallowed.


   On  success,  zero is returned.  On error, -1 is returned, and errno is
   set appropriately.


   EBADF  sockfd is not a valid file descriptor.

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

          The specified socket is not connected.

          The file descriptor sockfd does not refer to a socket.


   POSIX.1-2001,  POSIX.1-2008,  4.4BSD  (shutdown()  first  appeared   in


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


   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 domain sockets simply ignored invalid values.   This  problem  was
   fixed for UNIX domain sockets in Linux 3.7.


   connect(2), socket(2), socket(7)


   This  page  is  part of release 4.09 of the Linux man-pages project.  A
   description of the project, information about reporting bugs,  and  the
   latest     version     of     this    page,    can    be    found    at


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