SSL_LIBRARY_INIT(3) | Library Functions Manual | SSL_LIBRARY_INIT(3)

# NAME

`SSL_library_init`, `OpenSSL_add_ssl_algorithms`, `SSLeay_add_ssl_algorithms` — initialize SSL library by registering algorithms

# SYNOPSIS

library “libssl” libcrypto
`#include <openssl/ssl.h>`

int
`SSL_library_init`(void);

int
`OpenSSL_add_ssl_algorithms`(void);

int
`SSLeay_add_ssl_algorithms`(void);

# DESCRIPTION

These functions are deprecated. It is never useful for any application program to call any of them explicitly. The library automatically calls them internally whenever needed.

`SSL_library_init`() registers the available ciphers and digests which are used directly or indirectly by TLS.

`OpenSSL_add_ssl_algorithms`() and `SSLeay_add_ssl_algorithms`() are synonyms for `SSL_library_init`() and are implemented as macros.

# RETURN VALUES

`SSL_library_init`() always returns 1.

# SEE ALSO

ssl(3)

# HISTORY

`SSLeay_add_ssl_algorithms`() first appeared in SSLeay 0.8.0 and has been available since OpenBSD 2.4.

`SSL_library_init`() first appeared in OpenSSL 0.9.2b and has been available since OpenBSD 2.6.

`OpenSSL_add_ssl_algorithms`() first appeared in OpenSSL 0.9.5 and has been available since OpenBSD 2.7.

June 8, 2025 | Debian