Constructs patterns found in 'file'.
If id is -1, then all patterns found in 'file' are added to 'set'.
Otherwise, this function works exactly like FcFreeTypeQuery().
The number of faces in 'file' is returned in 'count'.
The number of patterns added to 'set' is returned.
FcBlanks is deprecated, blanks
is ignored and
accepted only for compatibility with older code.