Markus wrote:

I still think that there is no need to specify, if the engine should return success or error to an aborted genmove.

What I think wms meant (and what I tried to quote ...) was:

every command should either succeed or fail. when it succeeds, it could output it results, if any. If it fails, it issues a simple error message/reason. Aborting a command should be considered an error (from the command's perspective): the aborted command should result in an "?123 command aborted\n\n" reply.

There is no timing problem possible here: it is either succeed, or fail. If the abort is received too late, the command will already have reported it's success, and the abort will of course fail.

I hope I summarised correctly.

AvK