pmem2_source_alignment3
Returns data source alignment
Usage
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#include <libpmem2.h>struct pmem2_source;int pmem2_source_alignment(const struct pmem2_source *source, size_t *alignment);
Overview
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:
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PMEM2_E_INVALID_ALIGNMENT_VALUE- operating system returned unexpected alignment value (eg. it is not a power of two).
on Linux:
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PMEM2_E_INVALID_FILE_TYPE- file descriptor points to a character device other than Device DAX.
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PMEM2_E_INVALID_ALIGNMENT_FORMAT- kernel query for Device DAX alignment returned data in invalid format.
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errnoset by failing fstat(2), while trying to validate the file descriptor.
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errnoset by failing realpath(3), while trying to determine whether fd points to a Device DAX.
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errnoset by failing read(2), while trying to determine Device DAX’s alignment.
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errnoset by failing strtoull(3), while trying to determine Device DAX’s alignment.
On FreeBSD:
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PMEM2_E_INVALID_FILE_TYPE- file descriptor points to a directory, block device, pipe, socket, or character device.
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errnoset by failing fstat(2), while trying to validate the file descriptor.
Releases
3 releases since Debian 11 (Bullseye); the text changed 2 times.