Returns all keys for the group name group_name.
The array of returned keys will be null-terminated, so length may optionally
be null. In the event that the group_name cannot be found,
null is returned and throws is set to
GROUP_NOT_FOUND.
| this |
a KeyFile |
| group_name |
a group name |
| length |
return location for the number of keys returned, or null |
|
a newly-allocated null-terminated array of strings. Use strfreev to free it. |