NAME

       posix_fallocate - allocate file space

SYNOPSIS

       #include <fcntl.h>

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

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       posix_fallocate():
           _XOPEN_SOURCE >= 600 || _POSIX_C_SOURCE >= 200112L

DESCRIPTION

       The  function  posix_fallocate()  ensures  that  disk  space is allocated for the file referred to by the
       descriptor fd for the bytes in the range starting at offset  and  continuing  for  len  bytes.   After  a
       successful  call  to  posix_fallocate(), subsequent writes to bytes in the specified range are guaranteed
       not to fail because of lack of disk space.

       If the size of the file is less than offset+len, then the file is increased to this size;  otherwise  the
       file size is left unchanged.

RETURN VALUE

       posix_fallocate() returns zero on success, or an error number on failure.  Note that errno is not set.

ERRORS

       EBADF  fd is not a valid file descriptor, or is not opened for writing.

       EFBIG  offset+len exceeds the maximum file size.

       EINVAL offset was less than 0, or len was less than or equal to 0.

       ENODEV fd does not refer to a regular file.

       ENOSPC There is not enough space left on the device containing the file referred to by fd.

       ESPIPE fd refers to a pipe.

VERSIONS

       posix_fallocate() is available since glibc 2.1.94.

CONFORMING TO

       POSIX.1-2001.

       POSIX.1-2008  says  that  an  implementation shall give the EINVAL error if len was 0, or offset was less
       than 0.  POSIX.1-2001 says that an implementation shall give the EINVAL error if len is less than  0,  or
       offset was less than 0, and may give the error if len equals zero.

SEE ALSO

       fallocate(1), fallocate(2), lseek(2), posix_fadvise(2)

COLOPHON

       This  page  is  part  of  release 3.54 of the Linux man-pages project.  A description of the project, and
       information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.