close(2)                         UNIX System V                         close(2)


NAME
      close - close a file descriptor

SYNOPSIS
      #include <unistd.h>
      int close(int fildes);

DESCRIPTION
      fildes is a file descriptor obtained from a creat, open, dup, fcntl,
      pipe, or iocntl system call.  close closes the file descriptor indicated
      by fildes.  All outstanding record locks owned by the process (on the
      file indicated by fildes) are removed.

      When all file descriptors associated with the open file description have
      been closed, the open file description is freed.

      If the link count of the file is zero, when all file descriptors
      associated with the file have been closed, the space occupied by the file
      is freed and the file is no longer accessible.

      If a STREAMS-based [see intro(2)] fildes is closed, and the calling
      process had previously registered to receive a SIGPOLL signal [see
      signal(2)] for events associated with that stream [see I_SETSIG in
      streamio(7)], the calling process will be unregistered for events
      associated with the stream.  The last close for a stream causes the
      stream associated with fildes to be dismantled.  If O_NDELAY and
      O_NONBLOCK are clear and there have been no signals posted for the
      stream, and if there are data on the module's write queue, close waits up
      to 15 seconds (for each module and driver) for any output to drain before
      dismantling the stream.  The time delay can be changed via an I_SETCLTIME
      ioctl request [see streamio(7)].  If O_NDELAY or O_NONBLOCK is set, or if
      there are any pending signals, close does not wait for output to drain,
      and dismantles the stream immediately.

      If fildes is associated with one end of a pipe, the last close causes a
      hangup to occur on the other end of the pipe.  In addition, if the other
      end of the pipe has been named [see fattach(3C)], the last close forces
      the named end to be detached [see fdetach(3C)].  If the named end has no
      open processes associated with it and becomes detached, the stream
      associated with that end is also dismantled.

      The named file is closed unless one or more of the following are true:

      EBADF          fildes is not a valid open file descriptor.

      EINTR          A signal was caught during the close system call.

      ENOLINK        fildes is on a remote machine and the link to that machine
                     is no longer active.





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close(2)                         UNIX System V                         close(2)


SEE ALSO
      creat(2), dup(2), exec(2), fcntl(2), intro(2), open(2), pipe(2),
      signal(2), signal(5), streamio(7).
      fattach(3C), fdetach(3C) in the Programmer's Guide: Networking
      Interfaces.

DIAGNOSTICS
      Upon successful completion, a value of 0 is returned.  Otherwise, a value
      of -1 is returned and errno is set to indicate the error.













































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