dg_unbuffered_write(2)           DG/UX 5.4.2          dg_unbuffered_write(2)


NAME
       dgunbufferedwrite - synchronously write data to a file without
       system buffering

SYNOPSIS
       int dgunbufferedwrite(fildes, buffer, startblock, numblocks)
       int      fildes;
       char     buffer[];
       unsigned startblock;
       unsigned numblocks;

   where:
       fildes         An active descriptor

       buffer         User data buffer

       startblock    Starting logical block of request

       numblocks     Size (in blocks) of the request

DESCRIPTION
       The dgunbufferedwrite system call transfers numblocks 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
       startblock.

       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
       timelastaccessed, timelastmodified, or timelastchanged 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..numblocks
              Completed successfully.  The number of blocks actually written
              is returned.

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

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



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

dg_unbuffered_write(2)           DG/UX 5.4.2          dg_unbuffered_write(2)


       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
       dgunbufferedread(2), open(2), write(2).














































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