.\"	$OpenBSD: SSL_session_reused.3,v 1.6 2019/06/12 09:36:30 schwarze Exp $
.\"	OpenSSL b97fdb57 Nov 11 09:33:09 2016 +0100
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.Dd $Mdocdate: June 12 2019 $
.Dt SSL_SESSION_REUSED 3
.Os
.Sh NAME
.Nm SSL_session_reused
.Nd query whether a reused session was negotiated during handshake
.Sh SYNOPSIS
.In openssl/ssl.h
.Ft int
.Fn SSL_session_reused "SSL *ssl"
.Sh DESCRIPTION
Query whether a reused session was negotiated during the handshake.
.Pp
During the negotiation, a client can propose to reuse a session.
The server then looks up the session in its cache.
If both client and server agree on the session,
it will be reused and a flag is set that can be queried by the application.
.Sh RETURN VALUES
The following return values can occur:
.Bl -tag -width Ds
.It 0
A new session was negotiated.
.It 1
A session was reused.
.El
.Sh SEE ALSO
.Xr ssl 3 ,
.Xr SSL_ctrl 3 ,
.Xr SSL_CTX_set_session_cache_mode 3 ,
.Xr SSL_set_session 3
.Sh HISTORY
.Fn SSL_session_reused
first appeared in SSLeay 0.8.0 and has been available since
.Ox 2.4 .