pmem2_source_alignment - Man Page
returns data source alignment
Synopsis
#include <libpmem2.h> struct pmem2_source; int pmem2_source_alignment(const struct pmem2_source *source, size_t *alignment);
Description
The pmem2_source_alignment() function retrieves the alignment of offset and length needed for pmem2_map_new(3) to succeed. The alignment is stored in *alignment.
Return Value
The pmem2_source_alignment() function returns 0 on success. If the function fails, the *alignment variable is left unmodified and a negative error code is returned.
Errors
The pmem2_source_alignment() can fail with the following errors:
On all systems:
- PMEM2_E_INVALID_ALIGNMENT_VALUE - operating system returned unexpected alignment value (eg. it is not a power of two).
on Linux:
- PMEM2_E_INVALID_FILE_TYPE - file descriptor points to a character device other than Device DAX.
- PMEM2_E_INVALID_ALIGNMENT_FORMAT - kernel query for Device DAX alignment returned data in invalid format.
- -errno set by failing fstat(2), while trying to validate the file descriptor.
- -errno set by failing realpath(3), while trying to determine whether fd points to a Device DAX.
- -errno set by failing read(2), while trying to determine Device DAX’s alignment.
- -errno set by failing strtoull(3), while trying to determine Device DAX’s alignment.
On FreeBSD:
- PMEM2_E_INVALID_FILE_TYPE - file descriptor points to a directory, block device, pipe, socket, or character device.
- -errno set by failing fstat(2), while trying to validate the file descriptor.
See Also
errno(3), fstat(2), realpath(3), read(2), strtoull(3), pmem2_config_new(3), pmem2_source_from_handle(3), pmem2_source_from_fd(3), libpmem2(7) and <https://pmem.io>
Referenced By
pmem2_config_set_length(3), pmem2_config_set_offset(3), pmem2_map_new(3).
2023-06-05 PMDK - PMDK Programmer's Manual