- const char **gd_vector_list(DIRFILE *dirfile);
The dirfile argument must point to a valid DIRFILE object previously created by a call to gd_open(3).
The array returned will be de-allocated by a call to gd_close(3) and should not be de-allocated by the caller. The list returned should not be assumed to be in any particular order. The array is terminated by a NULL pointer. The number of strings in the array can be obtained from a call to gd_nvectors(3).
The caller may not modify any strings in the array, or the array itself. Doing so may cause database corruption. The pointer returned is guaranteed to be valid until gd_vector_list() is called again on the same DIRFILE object, or until the array is de-allocated by a call to gd_close(3).
RETURN VALUEUpon successful completion, gd_vector_list() returns a pointer to an array of strings containing the names of all the vector fields defined in the dirfile database. On error it returns NULL and sets the dirfile error to a non-zero error value. Possible error values are:
- The library was unable to allocate memory.
- The supplied dirfile was invalid.