opensolaris man page for posix_fallocate

posix_fallocate(3C)					   Standard C Library Functions 				       posix_fallocate(3C)

NAME
       posix_fallocate - file space control

SYNOPSIS
       #include <fcntl.h>

       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 continuing 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. Otherwise, the file size is
       not changed.

       Space allocated with posix_fallocate() is freed by a successful 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 off-
       set+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 maximum 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 underlying file system does  not
		 support this operation.

       EIO	 An I/O error occurred while reading from or writing 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 attributes:

       +-----------------------------+-----------------------------+
       |      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							    14 Jul 2008 					       posix_fallocate(3C)