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gpfs_cmp_fssnapid() Subroutine
Name
gpfs_cmp_fssnapid() - Compares two snapshot IDs for the same file system to determine the order in
which the two snapshots were taken.
Library
GPFS Library (libgpfs.a for AIX, libgpfs.so for Linux)
Synopsis
#include
int gpfs_cmp_fssnapid (const gpfs_fssnap_id_t *fssnapId1,
const gpfs_fssnap_id_t *fssnapId2,
int *result);
Description
The gpfs_cmp_fssnapid() subroutine compares two snapshot IDs for the same file system to determine
the order in which the two snapshots were taken. The result parameter is set as follows:
v result less than zero indicates that snapshot 1 was taken before snapshot 2.
v result equal to zero indicates that snapshot 1 and 2 are the same.
v result greater than zero indicates that snapshot 1 was taken after snapshot 2.
Notes:
1. Compile any program that uses this subroutine with the -lgpfs flag from the following library:
v libgpfs.a for AIX
v libgpfs.so for Linux
Parameters
fssnapId1 File system snapshot ID of the first snapshot.
fssnapId2 File system snapshot ID of the second snapshot.
result Pointer to an integer indicating the outcome of the comparison.
Exit status
If the gpfs_cmp_fssnapid() subroutine is successful, it returns a value of 0 and the result parameter is
set as described above.
If the gpfs_cmp_fssnapid() subroutine is unsuccessful, it returns a value of -1 and the global error
variable errno is set to indicate the nature of the error.
Exceptions
None.
Error status
EDOM The two snapshots cannot be compared because they were taken from two different file
systems.
ENOSYS The gpfs_cmp_fssnapid() subroutine is not available.
GPFS_E_INVAL_FSSNAPHANDLE
The file system snapshot handle is not valid.
Chapter 9. GPFS programming interfaces 281