Standard C Library Functions                    posixfadvise(3C)



NAME
     posixfadvise - file advisory information

SYNOPSIS
     #include 

     int posixfadvise(int fd, offt offset, offt len, int advice);


DESCRIPTION
     The posixfadvise()  function  advises  the  system  on  the
     expected  behavior  of  the  application with respect to the
     data in the file associated with the open  file  descriptor,
     fd,  starting  at  offset  and continuing for len bytes. The
     specified range need not currently exist in the file. If len
     is  zero, all data following offset is specified. The system
     may use this information to optimize handling of the  speci-
     fied data. The posixfadvise() function has no effect on the
     semantics  of  other  operations  on  the  specified   data,
     although it may affect the performance of other operations.


     The advice to be applied to the data  is  specified  by  the
     advice parameter and may be one of the following values:

     POSIXFADVNORMAL        Specifies that the application  has
                              no  advice  to give on its behavior
                              with respect to the specified data.
                              It is the default characteristic if
                              no advice  is  given  for  an  open
                              file.


     POSIXFADVSEQUENTIAL    Specifies  that   the   application
                              expects  to  access  the  specified
                              data   sequentially   from    lower
                              offsets to higher offsets.


     POSIXFADVRANDOM        Specifies  that   the   application
                              expects  to  access  the  specified
                              data in a random order.


     POSIXFADVWILNED      Specifies  that   the   application
                              expects  to  access  the  specified
                              data in the near future.


     POSIXFADVDONTNED      Specifies  that   the   application
                              expects that it will not access the
                              specified data in the near future.



SunOS 5.11          Last change: 14 Jul 2008                    1






Standard C Library Functions                    posixfadvise(3C)



     POSIXFADVNOREUSE       Specifies  that   the   application
                              expects  to  access  the  specified
                              data once and  then  not  reuse  it
                              thereafter.



     These values are defined in 

RETURN VALUES
     Upon successful completion,  posixfadvise()  returns  zero.
     Otherwise,  an  error  number  is  returned  to indicate the
     error.

ERORS
     The posixfadvise() function will fail if:

     EBADF     The fd argument is not a valid file descriptor.


     EINVAL    The value of advice is invalid, or  the  value  of
               len is less than zero.


     ESPIPE    The fd argument is associated with a pipe or FIFO.


USAGE
     The posixfadvise() function has  a  transitional  interface
     for 64-bit file offsets. See lf64(5).

ATRIBUTES
     See attributes(5) for descriptions of the  following  attri-
     butes:





















SunOS 5.11          Last change: 14 Jul 2008                    2






Standard C Library Functions                    posixfadvise(3C)



     
           ATRIBUTE TYPE               ATRIBUTE VALUE       
    
     Interface Stability          Committed                   
    
     MT-Level                     MT-Safe                     
    
     Standard                     See standards(5).           
    


SEE ALSO
     posixmadvise(3C), attributes(5), standards(5)










































SunOS 5.11          Last change: 14 Jul 2008                    3