uio(9s) 																   uio(9s)

NAME

       uio - General: Describes I/O, either single vector or multiple vectors

SYNOPSIS

       -----------------------------
       Member Name   Data Type
       -----------------------------
       uio_iov	     struct iovec *
       uio_iovcnt    int
       uio_offset    off_t
       uio_segflg    enum uio_seg
       uio_resid     int
       uio_rw	     enum uio_rw
       -----------------------------

MEMBERS

       Specifies  a  pointer  to the first iovec structure. The iovec structure has two members: one that specifies the address of the segment and
       another that specifies the size of the segment. The system allocates contiguous iovec structures for a given transfer.  Specifies the  num-
       ber  of	iovec  structures for this transfer.  Specifies the offset within the file.  Specifies the segment type. This member can be set to
       one of the following values: UIO_USERSPACE (the segment is from the user data space), UIO_SYSSPACE (the segment is from the system  space),
       or  UIO_USERISPACE  (the  segment  is  from the user I space).  Specifies the number of bytes that still need to be transferred.  Specifies
       whether the transfer is a read or a write. This member is set by read and write system calls according to the corresponding  field  in  the
       file  descriptor. This member can be set to one of the following values: UIO_READ (read transfer), UIO_WRITE (write transfer), or UIO_AIORW
       (Alpha I/O read/write transfer).

DESCRIPTION

       The uio data structure describes, either singler-vector or multiple-vector I/O. Typically, kernel modules do not manipulate the members	of
       this  data structure. However, the data structure is presented here for the purpose of understanding the uiomove routine, which operates on
       the members of the uio structure.

FILES

SEE ALSO

       Routines: uiomove(9r)

																	   uio(9s)