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                                                                 close(2)



        _________________________________________________________________
        close                                                 System Call
        Close an object associated with a file descriptor.
        _________________________________________________________________


        SYNTAX

        int   close  (fildes)
        int             fildes;


        PARAMETERS

        fildes         A valid, active file descriptor.


        DESCRIPTION

        If <fildes> is a valid, active descriptor, close breaks the
        connection between the descriptor indicated by <fildes> and the
        object to which it refers.  If <fildes> is the last descriptor
        that refers to an object pointer, the object pointer is "closed"
        by invoking the type- specific close operation.

        Thus, the type manager is informed only of the last close
        operation of an object pointer.  These managers (and
        specifically, the device driver close operations) should not
        expect to be invoked during each close system call.

        Upon completion of the close operation, <fildes> will be
        inactive. Until <fildes> is reallocated, subsequent operations
        using <fildes> will result in an EBADF error condition.

        Objects are also subject to implicit close operations via the
        exit and exec operations.  When a process terminates, all active
        descriptors are closed.  When a process performs a successful
        exec operation, all active descriptors with the `close-on-exec'
        attribute are closed.  These implicit close operations are
        equivalent to an explicit close operation.

        On each successful close of an object, all outstanding locks
        owned by the calling process on the object are released.


        ACCESS CONTROL

        None.






        DG/UX 4.00                                                 Page 1
               Licensed material--property of copyright holder(s)





                                                                 close(2)



        RETURN VALUE

        0              The object was successfully closed.


        -1             An error occurred.  Errno is set to indicate the
                       error.


        EXCEPTIONS

        Errno may be set to one of the following error codes:


        EBADF          <Fildes> is not a valid, active descriptor.


        EINTR          Close call was interrupted.


        EIO            An i/o error occurred while reading from or
                       writing to the file system.


        SEE ALSO

        The related manual sections:  accept(2), creat(2), dup(2),
        exec(2), fcntl(2), open(2), pipe(2), signal(2), sigset(2),
        socket(2), socketpair(2).

























        DG/UX 4.00                                                 Page 2
               Licensed material--property of copyright holder(s)



Typewritten Software • bear@typewritten.org • Edmonds, WA 98026