Manual Pages for UNIX Operating System command usage for man posix_fallocate

Standard C Library Functions                  posix_fallocate(3C)



NAME
     posix_fallocate - file space control

SYNOPSIS
     #include 

     int posix_fallocate(int fd, off_t offset, off_t len);


DESCRIPTION
     The posix_fallocate() function  ensures  that  any  required
     storage  for  regular  file data starting at offset and con-
     tinuing for len  bytes  is  allocated  on  the  file  system
     storage  media.  If  posix_fallocate() returns successfully,
     subsequent writes to the specified file data will  not  fail
     due  to  the  lack  of free space on the file system storage
     media.


     If the offset+len is beyond  the  current  file  size,  then
     posix_fallocate()  adjusts the file size to offset+len. Oth-
     erwise, the file size is not changed.


     Space allocated with posix_fallocate() is freed  by  a  suc-
     cessful  call to creat(2) or open(2) that truncates the size
     of the file. Space allocated with posix_fallocate()  may  be
     freed by a successful call to ftruncate(3C) that reduces the
     file size to a size smaller than offset+len.

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

ERRORS
     The posix_fallocate() function will fail if:

     EBADF     The fd argument is not a valid file descriptor  or
               references  a  file  that was opened without write
               permission.


     EFBIG     The value of offset+len is greater than  the  max-
               imum file size.


     EINTR     A signal was caught during execution.


     EINVAL    The len argument is less than or equal to zero, or
               the  offset  argument  is  less  than zero, or the



SunOS 5.11          Last change: 14 Jul 2008                    1






Standard C Library Functions                  posix_fallocate(3C)



               underlying  file  system  does  not  support  this
               operation.


     EIO       An I/O error occurred while reading from or  writ-
               ing to a file system.


     ENODEV    The fd argument does not refer to a regular file.


     ENOSPC    There is insufficient free space remaining on  the
               file system storage media.


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


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

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



     ____________________________________________________________
    |       ATTRIBUTE TYPE        |       ATTRIBUTE VALUE       |
    |_____________________________|_____________________________|
    | Interface Stability         | Committed                   |
    |_____________________________|_____________________________|
    | MT-Level                    | MT-Safe                     |
    |_____________________________|_____________________________|
    | Standard                    | See standards(5).           |
    |_____________________________|_____________________________|


SEE ALSO
     creat(2), open(2), unlink(2), ftruncate(3C),  attributes(5),
     standards(5)













SunOS 5.11          Last change: 14 Jul 2008                    2