FEN fullmove number zero

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casaschi
Posts: 164
Joined: Wed Dec 23, 2009 1:57 pm

FEN fullmove number zero

Post by casaschi »

While playing with my new PGN parser, someone pointed out to me a very common error in the FEN strings used for non standard starting positions: the last parameter of the FEN string is the "fullmove number" that should be a number starting from 1, while very often this is set (incorrectly) as 0.

Exmple, this is the FEN string of the usual starting position:

rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1

The errored version of it would be:

rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 0

No big deal to cope with it, just assume 1 when the value of 0 is read, but I was just curious, do you know which software is culpable of spreading out those wrong FEN strings?

I checked scid and winboard and their FEN strings are OK...