|POSIX_FALLOCATE(3P)||POSIX Programmer's Manual||POSIX_FALLOCATE(3P)|
int posix_fallocate(int fd, off_t offset, off_t len);
If the offset+len is beyond the current file size, then posix_fallocate() shall adjust the file size to offset+len. Otherwise, the file size shall not be changed.
It is implementation-defined whether a previous posix_fadvise() call influences allocation strategy.
Space allocated via posix_fallocate() shall be freed by a successful call to creat() or open() that truncates the size of the file. Space allocated via posix_fallocate() may be freed by a successful call to ftruncate() that reduces the file size to a size smaller than offset+len.
- The fd argument is not a valid file descriptor.
- The fd argument references a file that was opened without write permission.
- The value of offset+len is greater than the maximum file size.
- A signal was caught during execution.
- The len argument is less than zero, or the offset argument is less than zero, or the underlying file system does not support this operation.
- An I/O error occurred while reading from or writing to a file system.
- The fd argument does not refer to a regular file.
- There is insufficient free space remaining on the file system storage media.
- The fd argument is associated with a pipe or FIFO.
The posix_fallocate() function may fail if:
- The len argument is zero.
The following sections are informative.
The Base Definitions volume of POSIX.1‐2008, <fcntl.h>
Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .
|2013||IEEE/The Open Group|