What does the term "safe interrupt" mean?

Question

I meet this term from time to time. And now I really need a clear explanation as I want to use some MPI routines that say they are not safe to interrupt.

Answer 1

I believe this is a different wording for reentrant. If the function is reentrant , it can be interrupted in the middle, and call.

For instance:

void function()
{
    lock(mtx);
    /* code ... */
    unlock(mtx);
}

( ). lock(mtx) , , . , .

Answer 2

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