#include <openssl/err.h> int ERR_set_mark(void); int ERR_pop_to_mark(void); int ERR_clear_last_mark(void);
ERR_pop_to_mark() 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 removed.
ERR_clear_last_mark() removes the last mark added if there is one.
ERR_clear_last_mark() and ERR_pop_to_mark() return 0 if there was no mark in the error stack, which implies that the stack became empty, otherwise 1.
Licensed under the Apache License 2.0 (the ``License''). You may not use this file except in compliance with the License. You can obtain a copy in the file LICENSE in the source distribution or at <https://www.openssl.org/source/license.html>.