1=pod 2 3=head1 NAME 4 5OPENSSL_fork_prepare, 6OPENSSL_fork_parent, 7OPENSSL_fork_child 8- OpenSSL fork handlers 9 10=head1 SYNOPSIS 11 12 #include <openssl/crypto.h> 13 14 void OPENSSL_fork_prepare(void); 15 void OPENSSL_fork_parent(void); 16 void OPENSSL_fork_child(void); 17 18=head1 DESCRIPTION 19 20OpenSSL has state that should be reset when a process forks. For example, 21the entropy pool used to generate random numbers (and therefore encryption 22keys) should not be shared across multiple programs. 23The OPENSSL_fork_prepare(), OPENSSL_fork_parent(), and OPENSSL_fork_child() 24functions are used to reset this internal state. 25 26Platforms without fork(2) will probably not need to use these functions. 27Platforms with fork(2) but without pthread_atfork(3) will probably need 28to call them manually, as described in the following paragraph. Platforms 29such as Linux that have both functions will normally not need to call these 30functions as the OpenSSL library will do so automatically. 31 32L<OPENSSL_init_crypto(3)> will register these functions with the appropriate 33handler, when the B<OPENSSL_INIT_ATFORK> flag is used. For other 34applications, these functions can be called directly. They should be used 35according to the calling sequence described by the pthread_atfork(3) 36documentation, which is summarized here. OPENSSL_fork_prepare() should 37be called before a fork() is done. After the fork() returns, the parent 38process should call OPENSSL_fork_parent() and the child process should 39call OPENSSL_fork_child(). 40 41=head1 RETURN VALUES 42 43OPENSSL_fork_prepare(), OPENSSL_fork_parent() and OPENSSL_fork_child() do not 44return values. 45 46=head1 SEE ALSO 47 48L<OPENSSL_init_crypto(3)> 49 50=head1 HISTORY 51 52These functions were added in OpenSSL 1.1.1. 53 54=head1 COPYRIGHT 55 56Copyright 2017-2019 The OpenSSL Project Authors. All Rights Reserved. 57 58Licensed under the OpenSSL license (the "License"). You may not use 59this file except in compliance with the License. You can obtain a copy 60in the file LICENSE in the source distribution or at 61L<https://www.openssl.org/source/license.html>. 62 63=cut 64