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POSIX_FADVISE(2)              System Calls Manual             POSIX_FADVISE(2)

NAME
     posix_fadvise - hint at the future access pattern of a file

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <fcntl.h>

     int
     posix_fadvise(int fd, off_t offset, off_t size, int hint);

DESCRIPTION
     posix_fadvise() hints at the application's access pattern to the file and
     range given by the file descriptor, fd, and offset and size.  If size is
     zero, it means to the end of file.

     hint should be one of the following:

           POSIX_FADV_NORMAL      No hint.  (default)
           POSIX_FADV_RANDOM      Random access.
           POSIX_FADV_SEQUENTIAL  Sequential access.  (from lower offset to
                                  higher offset.)
           POSIX_FADV_WILLNEED    Will be accessed.
           POSIX_FADV_DONTNEED    Will not be accessed.
           POSIX_FADV_NOREUSE     Will be accessed just once.

     Calling posix_fadvise() doesn't alter the semantics of the operations, it
     is only a matter of performance.

RETURN VALUES
     On success, posix_fadvise() returns 0.  Otherwise, it returns an error
     number.

SEE ALSO
     errno(2), madvise(2)

BUGS
     For POSIX_FADV_NORMAL, POSIX_FADV_RANDOM, and POSIX_FADV_SEQUENTIAL, the
     current implementation ignores offset and size, and applies the hint to
     the whole file.

NetBSD 10.99                   February 4, 2013                   NetBSD 10.99