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OPENSSL_fork_prepare(3)             OpenSSL            OPENSSL_fork_prepare(3)

       OPENSSL_fork_prepare, OPENSSL_fork_parent, OPENSSL_fork_child - OpenSSL
       fork handlers

       libcrypto, -lcrypto

        #include <openssl/crypto.h>

        void OPENSSL_fork_prepare(void);
        void OPENSSL_fork_parent(void);
        void OPENSSL_fork_child(void);

       OpenSSL has state that should be reset when a process forks. For
       example, the entropy pool used to generate random numbers (and
       therefore encryption keys) should not be shared across multiple
       programs.  The OPENSSL_fork_prepare(), OPENSSL_fork_parent(), and
       OPENSSL_fork_child() functions are used to reset this internal state.

       Platforms without fork(2) will probably not need to use these
       functions.  Platforms with fork(2) but without pthread_atfork(3) will
       probably need to call them manually, as described in the following
       paragraph.  Platforms such as Linux that have both functions will
       normally not need to call these functions as the OpenSSL library will
       do so automatically.

       OPENSSL_init_crypto(3) will register these functions with the
       appropriate handler, when the OPENSSL_INIT_ATFORK flag is used. For
       other applications, these functions can be called directly. They should
       be used according to the calling sequence described by the
       pthread_atfork(3) documentation, which is summarized here.
       OPENSSL_fork_prepare() should be called before a fork() is done.  After
       the fork() returns, the parent process should call
       OPENSSL_fork_parent() and the child process should call

       OPENSSL_fork_prepare(), OPENSSL_fork_parent() and OPENSSL_fork_child()
       do not return values.


       These functions were added in OpenSSL 1.1.1.

       Copyright 2017-2019 The OpenSSL Project Authors. All Rights Reserved.

       Licensed under the OpenSSL license (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

1.1.1i                            2020-01-23           OPENSSL_fork_prepare(3)