pmem2_source_device_id() - returns the unique identifier of
a device
-
#include <libpmem2.h>
struct pmem2_source;
int pmem2_source_device_id(const struct pmem2_source *source, char *id, size_t *len);
The pmem2_source_device_id() function retrieves a unique
identifier of all NVDIMMs backing the data source. This function has two
operating modes:
- •
- if *id is NULL the function calculates a buffer length required for
storing the identifier of the *source device and puts this length
in *len The more hardware devices back the data source, the longer
the length is.
- •
- if *id is not NULL it must point to a buffer of length *len
provided by the previous call to this function. On success,
pmem2_source_device_id() will store a unique identifier of all
hardware devices backing the data source.
For details on how to use the unique identifier for detecting
the unsafe shutdown please refer to
libpmem2_unsafe_shutdown(7) manual page.
The pmem2_source_device_id() function returns 0 on success.
If the function fails, the *id and *len variables contents are
left unmodified and a negative error code is returned.
The pmem2_source_device_id() can fail with the following
errors:
On all systems:
- •
- PMEM2_E_BUFFER_TOO_SMALL - the provided buffer of length
*len is too small to store the full identifier of the backing
devices.
- •
- PMEM2_E_NOSUPP - the underlying platform does not expose hardware
identification.
On Windows:
- •
- -errno equivalent of return code set by failing
GetFinalPathNameByHandleW(), while trying to resolve the volume
path from the file handle.
- •
- -errno set by failing malloc(3), while trying to allocate a
buffer for storing volume path.
- •
- -errno equivalent of return code set by failing
CreateFileW(), while trying to obtain a handle to the volume.
- •
- -errno equivalent of return code set by failing
DeviceIoControl(), while trying to obtain volume USC
value.
On Linux:
- •
- -errno set by failing fstat(2), while trying to validate the
file descriptor.
- •
- -errno set by failing ndctl_new(), while trying to initiate
a new NDCTL library context.