ERR_set_mark, ERR_pop_to_mark - set marks and pop errors until mark
sets a mark on the current topmost error record if there
will pop the top of the error stack until a mark is
found. The mark is then removed. If there is no mark, the whole stack is
returns 0 if the error stack is empty, otherwise 1.
returns 0 if there was no mark in the error stack,
which implies that the stack became empty, otherwise 1.
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Licensed under the OpenSSL license (the "License"). You may not use
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