+ Retrieves the next valid token number in a given namespace. \r
+ \r
+ This is useful since the PCD infrastructure contains a sparse list of token numbers, \r
+ and one cannot a priori know what token numbers are valid in the database. \r
+ \r
+ If TokenNumber is 0 and Guid is not NULL, then the first token from the token space specified by Guid is returned. \r
+ If TokenNumber is not 0 and Guid is not NULL, then the next token in the token space specified by Guid is returned. \r
+ If TokenNumber is 0 and Guid is NULL, then the first token in the default token space is returned. \r
+ If TokenNumber is not 0 and Guid is NULL, then the next token in the default token space is returned. \r
+ The token numbers in the default token space may not be related to token numbers in token spaces that are named by Guid. \r
+ If the next token number can be retrieved, then it is returned in TokenNumber, and EFI_SUCCESS is returned. \r
+ If TokenNumber represents the last token number in the token space specified by Guid, then EFI_NOT_FOUND is returned. \r
+ If TokenNumber is not present in the token space specified by Guid, then EFI_NOT_FOUND is returned.\r
+\r