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Sortix nightly manual

This manual documents Sortix nightly, a development build that has not been officially released. You can instead view this document in the latest official manual.

NAME

SSL_set_fd, SSL_set_rfd, SSL_set_wfd — connect the SSL object with a file descriptor

SYNOPSIS

#include <openssl/ssl.h>
int
SSL_set_fd(SSL *ssl, int fd);
int
SSL_set_rfd(SSL *ssl, int fd);
int
SSL_set_wfd(SSL *ssl, int fd);

DESCRIPTION

SSL_set_fd() sets the file descriptor fd as the input/output facility for the TLS/SSL (encrypted) side of ssl. fd will typically be the socket file descriptor of a network connection.
When performing the operation, a socket BIO is automatically created to interface between the ssl and fd. The BIO and hence the SSL engine inherit the behaviour of fd. If fd is non-blocking, the ssl will also have non-blocking behaviour.
If there was already a BIO connected to ssl, BIO_free(3) will be called (for both the reading and writing side, if different).
SSL_set_rfd() and SSL_set_wfd() perform the respective action, but only for the read channel or the write channel, which can be set independently.

RETURN VALUES

The following return values can occur:
0
The operation failed. Check the error stack to find out why.
1
The operation succeeded.

SEE ALSO

BIO_new(3), ssl(3), SSL_accept(3), SSL_connect(3), SSL_get_fd(3), SSL_set_bio(3), SSL_shutdown(3)

HISTORY

SSL_set_fd() appeared in SSLeay 0.4 or earlier. SSL_set_rfd() and SSL_set_wfd() first appeared in SSLeay 0.6.0. These functions have been available since OpenBSD 2.4.
Copyright 2011-2025 Jonas 'Sortie' Termansen and contributors.
Sortix's source code is free software under the ISC license.
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