int genders_getnodes(genders_t handle, char *nodes, int len, const char *attr, const char *val);
genders_getnodes() gets the names of nodes in the genders file that have the attribute specified by attr and the value specified by val. The nodes are stored in the list pointed to by nodes. len indicates the number of nodes that can be stored in the list. If attr is NULL, genders_getnodes() returns all the nodes listed in the genders file. If val is NULL, attribute values are ignored.
To avoid passing in a list that is not large enough to store all the nodes, genders_getnumnodes(3) should be used to determine the minimum number of elements nodes should be able to store. genders_nodelist_create(3) could be used to create a list that is guaranteed to be large enough to store all of the nodes.
On success, the number of nodes stored in nodes is returned. On error, -1 is returned, and an error code is returned in handle. The error code can be retrieved via genders_errnum(3) , and a description of the error code can be retrieved via genders_strerror(3). Error codes are defined in genders.h.
The handle parameter is NULL. The genders handle must be created with genders_handle_create(3).
genders_load_data(3) has not been called to load genders data.
The list pointed to by nodes is not large enough to store all the nodes.
An incorrect parameter has been passed in.
A null pointer has been found in the list passed in.
handle has an incorrect magic number. handle does not point to a genders handle or handle has been destroyed by genders_handle_destroy(3).
libgenders(3), genders_handle_create(3), genders_load_data(3), genders_getnumnodes(3), genders_nodelist_create(3), genders_errnum(3), genders_strerror(3)
genders_index_attrvals(3), genders_nodelist_create(3), libgenders(3).