dgunbufferedwrite(2)     DG/UX 4.30      dgunbufferedwrite(2)



     NAME
          dg_unbuffered_write - Synchronously write data to a file
          without system buffering

     SYNOPSIS
          int   dg_unbuffered_write  (fildes, buffer, start_block, num_blocks)
             int             fildes;
             char            buffer[];
             unsigned        start_block;
             unsigned        num_blocks;

     PARAMETERS
          fildes
               An active descriptor.

          buffer
               User data buffer.

          start_block
               Starting logical block of request.

          num_blocks
               Size (in blocks) of the request.

     DESCRIPTION
          The dgunbufferedwrite system call transfers num_blocks
          blocks of data from the buffer pointed to by buffer into the
          object associated with fildes.  The starting position of the
          request is given by start_block.

          The file position attribute of fildes is ignored by this
          interface.  The starting block position of the write must be
          specified in the call.  The file position attribute of
          fildes remains unchanged by the execution of this call.

          If the operation is successful, the inode is flushed out
          before control is returned to the user if any attribute
          other than time_last_accessed, time_last_modified, or
          time_last_changed of the file has changed.  Index blocks
          modified by this operation are also flushed before returning
          control to the user.

          If mandatory record locking is enabled for the file, this
          call will fail.

     ACCESS CONTROL
          The process must have write access to the descriptor fildes,
          and it must have been opened with the O_DG_UNBUFFERED open
          flag to allow for unbuffered I/O access.

     RETURN VALUE
          0..num_blocks



     Licensed material--property of copyright holder(s)         Page 1

     dgunbufferedwrite(2)     DG/UX 4.30      dgunbufferedwrite(2)



               Completed successfully.  The number of blocks actually
               written is returned.

          -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 opened for unbuffered writing.

          EFBIG
               An attempt was made to write a file that exceeds the
               process's file size limit or the maximum file size.

          EFAULT
               Buffer points outside the allocated address space.

          EINTR
               A signal was caught during the system call.

     SEE ALSO
          dg_unbuffered_read(2), open(2), write(2).
































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