SSL_GET_FD(3)              Library Functions Manual              SSL_GET_FD(3)

NAME
     SSL_get_fd, SSL_get_rfd, SSL_get_wfd - get file descriptor linked to an
     SSL object

SYNOPSIS
     #include <openssl/ssl.h>

     int
     SSL_get_fd(const SSL *ssl);

     int
     SSL_get_rfd(const SSL *ssl);

     int
     SSL_get_wfd(const SSL *ssl);

DESCRIPTION
     SSL_get_fd() returns the file descriptor which is linked to ssl.
     SSL_get_rfd() and SSL_get_wfd() return the file descriptors for the read
     or the write channel, which can be different.  If the read and the write
     channel are different, SSL_get_fd() will return the file descriptor of
     the read channel.

RETURN VALUES
     The following return values can occur:

     -1      The operation failed, because the underlying BIO is not of the
             correct type (suitable for file descriptors).

     >=0     The file descriptor linked to ssl.

SEE ALSO
     BIO_new(3), ssl(3), SSL_set_fd(3)

HISTORY
     SSL_get_fd() appeared in SSLeay 0.4 or earlier and has been available
     since OpenBSD 2.4.

     SSL_get_rfd() and SSL_get_wfd() first appeared in OpenSSL 0.9.6c and have
     been available since OpenBSD 3.2.

Linux 6.8.2-arch2-1             March 27, 2018             Linux 6.8.2-arch2-1