i've got a patch in which i need my keyboard's key-repeat function turned off. this is the function that allows you to hold down the 'a' key and get aaaaaaaaaaaa. it's easy to do this in a mac's system preferences, but i wonder is there a way to do this from pd, so it's all adjusted automatically when i open a patch

I don't know, but maybe [key]
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[change] will do what you want.
but what if you wanted the same key twice in a row...
you could try [key] [keyup]
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| [t b]
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[once]

...edit...I tried this out...keyup doesn't work like I thought - not like a midi keyboard - there is just a short delay and then it outputs the key number. Some combination of objects should work though.

Possibly using [shell] and there must be a terminal command.

[defaults write NSGlobalDomain KeyRepeat -int 9(
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[shell]

Maybe something like that. Though, I don't have OSX.