Persistent Memory Development Kit
This is examples/libpmemobj/array/README.
This directory contains an example application implemented using libpmemobj.
The array example allows to perform basic operations like allocation,
reallocation and de-allocation on persistent array. User can choose
size of new or reallocated array. There are also 3 types of elements which
are supported: int, PMEMoid and TOID with structure containing int variable.
Persistent pointer can be treated as a pointer to the first element of array.
TOID with user's defined structure can be allocated by using POBJ_ALLOC or
POBJ_ZALLOC macros (similarly when using PMEMoid there are pmemobj_alloc() and
pmemobj_zalloc() functions) with proper number elements multiplied by
user-defined structure's size. Access to array's elements can be executed by
using pmemobj_direct() function or just using proper macro.
For example D_RW(test1)[0] points to first element of test1 array.
To allocate new array using application run the following command:
$ array <file-name> alloc <array-name> <size> <type>
Where <file-name> is file where pool will be created or opened,
<array-name> is user's defined unique name, <size> is number of elements of
persistent array and <type> is one of listed: int, PMEMoid, TOID.
To reallocate existing array run the following command:
$ array <file-name> realloc <array-name> <size>
To free existing array run the following command:
$ array <file-name> free <array-name>
To print array's elements run the following command:
$ array <file-name> print <array-name>
Example of usage:
$ array /mnt/pmem/testfile alloc test1 10 TOID
$ array /mnt/pmem/testfile alloc test2 100 int
$ array /mnt/pmem/testfile realloc test1 50
$ array /mnt/pmem/testfile realloc test2 5
$ array /mnt/pmem/testfile print test1
$ array /mnt/pmem/testfile free test1
$ array /mnt/pmem/testfile free test2