1=pod 2 3=head1 NAME 4 5OPENSSL_init_ssl - OpenSSL (libssl and libcrypto) initialisation 6 7=head1 SYNOPSIS 8 9 #include <openssl/ssl.h> 10 11 int OPENSSL_init_ssl(uint64_t opts, const OPENSSL_INIT_SETTINGS *settings); 12 13=head1 DESCRIPTION 14 15During normal operation OpenSSL (libssl and libcrypto) will allocate various 16resources at start up that must, subsequently, be freed on close down of the 17library. Additionally some resources are allocated on a per thread basis (if the 18application is multi-threaded), and these resources must be freed prior to the 19thread closing. 20 21As of version 1.1.0 OpenSSL will automatically allocate all resources that it 22needs so no explicit initialisation is required. Similarly it will also 23automatically deinitialise as required. 24 25However, there may be situations when explicit initialisation is desirable or 26needed, for example when some nondefault initialisation is required. The 27function OPENSSL_init_ssl() can be used for this purpose. Calling 28this function will explicitly initialise BOTH libcrypto and libssl. To 29explicitly initialise ONLY libcrypto see the 30L<OPENSSL_init_crypto(3)> function. 31 32Numerous internal OpenSSL functions call OPENSSL_init_ssl(). 33Therefore, in order to perform nondefault initialisation, 34OPENSSL_init_ssl() MUST be called by application code prior to 35any other OpenSSL function calls. 36 37The B<opts> parameter specifies which aspects of libssl and libcrypto should be 38initialised. Valid options for libcrypto are described on the 39L<OPENSSL_init_crypto(3)> page. In addition to any libcrypto 40specific option the following libssl options can also be used: 41 42=over 4 43 44=item OPENSSL_INIT_NO_LOAD_SSL_STRINGS 45 46Suppress automatic loading of the libssl error strings. This option is 47not a default option. Once selected subsequent calls to 48OPENSSL_init_ssl() with the option 49B<OPENSSL_INIT_LOAD_SSL_STRINGS> will be ignored. 50 51=item OPENSSL_INIT_LOAD_SSL_STRINGS 52 53Automatic loading of the libssl error strings. This option is a 54default option. Once selected subsequent calls to 55OPENSSL_init_ssl() with the option 56B<OPENSSL_INIT_LOAD_SSL_STRINGS> will be ignored. 57 58=back 59 60OPENSSL_init_ssl() takes a B<settings> parameter which can be used to 61set parameter values. See L<OPENSSL_init_crypto(3)> for details. 62 63=head1 RETURN VALUES 64 65The function OPENSSL_init_ssl() returns 1 on success or 0 on error. 66 67=head1 SEE ALSO 68 69L<OPENSSL_init_crypto(3)> 70 71=head1 HISTORY 72 73The OPENSSL_init_ssl() function was added in OpenSSL 1.1.0. 74 75=head1 COPYRIGHT 76 77Copyright 2016-2020 The OpenSSL Project Authors. All Rights Reserved. 78 79Licensed under the OpenSSL license (the "License"). You may not use 80this file except in compliance with the License. You can obtain a copy 81in the file LICENSE in the source distribution or at 82L<https://www.openssl.org/source/license.html>. 83 84=cut 85