Returns non-zero if the format represented by \a first is a subset of
* the format represented by \a second. This means that \a second must
* have all the fields that \a first does, but the reverse need not
* be true. This is typically expected to be used to check if a
* stream's format is compatible with a given sink. In such a case,
* \a first would be the sink's format and \a second would be the
* stream's. \since 1.0
Returns non-zero if the format represented by \a first is a subset of * the format represented by \a second. This means that \a second must * have all the fields that \a first does, but the reverse need not * be true. This is typically expected to be used to check if a * stream's format is compatible with a given sink. In such a case, * \a first would be the sink's format and \a second would be the * stream's. \since 1.0