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c - single bit manipulation

is it possible to get just one bit of an int in C and then flip it without reading the entire int and writing it back to memory?

context: trying to avoid too many locks/unlocks in pthread.

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You can not read a single bit from the memory, actually you can not force CPU to read only a single byte. It is always reading a full cache line, which could have different sizes for different CPUs.

But from the language point of view you can use bit fields http://publications.gbdirect.co.uk/c_book/chapter6/bitfields.html


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