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How does Windows switch to supervisor mode during a system call?

How does Windows switch to supervisor mode during a system call? I heard something about trap 0, but it doesn't even look like an x86 instruction. I went through some system calls, but I cannot find them. Are there many Windows system calls in user mode? Which DO runs in supervisor mode?

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A system call is also known as a software interrupt. An x86 instruction that causes a software interrupt has a mnemonic INT . How data is transferred to the operating system is determined by the ABI operating system. As far as I know, Windows uses 0x80 at once for all its routines and sends additional data through registers, but I'm not sure. 0x20 is the first available immediately because the range from 0 to 31 is reserved and is used for general exceptions, such as integer division by zero and memory errors.

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Source: https://habr.com/ru/post/1722070/

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