A newbie question :-)

[Daniel Anulliero]

When I ' m working I think about my chess program ( also lol) and a trivial question come to my mind : Can I initialyse my hash structure with just

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memset (hash_struct,0,sizeof (hash_struct));

Is it safety?
I read all the advices on the Web : some guy says yes , some says no .
That is my newbie question of the day
Best
Dany

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[mar]

Depends on what type is hash_struct. If it's a struct, then you can with

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memset(&hash_struct, 0, sizeof(hash_struct));

If it's a pointer, then you should be able to do

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memset(hash_struct, 0, sizeof(*hash_struct));

[Henk]

Welcome to this website. We are always happy with new chess programmers. Maybe first step is to create a working chess engine using alpha beta search. And perhaps next step is to beat Fairy max or if that is too difficult Skipper chess engine in online chess tourney.

[Daniel Anulliero]

Welcome to this website. We are always happy with new chess programmers. Maybe first step is to create a working chess engine using alpha beta search. And perhaps next step is to beat Fairy max or if that is too difficult Skipper chess engine in online chess tourney.

Ahah you guy are very funny !
Well I never answer to yours silly / trolling topics since 2-3 months , very good if you do the same for my posts , please ignore me and concentrate your efforts to learn to skipper to play chess and listen à lot if can , the experts advices 😉

[Daniel Anulliero]

Thanks martin for your intelligent and constructive answer
Seems I'm not alone to think about this kind of existential question :
http://www.ex-parrot.com/~chris/random/initialise.html
Best
Dany

[ZirconiumX]

Hi Daniel! (Remember me from the HGM tourney?)

I personally follow the philosophy of "first get it working, then get it working well". Maybe memset is safe, maybe it isn't. I just initialise it manually. It's not time critical code, so paranoia is fine.

[Daniel Anulliero]

Hi Daniel! (Remember me from the HGM tourney?)

I personally follow the philosophy of "first get it working, then get it working well". Maybe memset is safe, maybe it isn't. I just initialise it manually. It's not time critical code, so paranoia is fine.

Of course I remember , Zirconium
Ok I will try to initialise by hand to see what happen...
Because I think I have some bugs in my zobrist scheme , I want to try all the possibilities

[mmcknight]

You don't even need to initialize. The default value will never match your hash index.

Matt

[ZirconiumX]

You don't even need to initialize. The default value will never match your hash index.

Matt

Accessing uninitialised data is just asking for trouble. And the likelihood of anything is never zero. Granted, the chance of the random data perfectly matching is 1 to 2^64, but not all engines store the entire hash in an entry.

[Daniel Anulliero]

You don't even need to initialize. The default value will never match your hash index.

Matt

Accessing uninitialised data is just asking for trouble. And the likelihood of anything is never zero. Granted, the chance of the random data perfectly matching is 1 to 2^64, but not all engines store the entire hash in an entry.

Indeed Mathew but I tested today with memset , it seems safe , all values was 0 .I must find TT bugs somewhere