.\"	$OpenBSD: SSL_CTX_flush_sessions.3,v 1.2 2016/11/30 13:19:54 schwarze Exp $
.\"	OpenSSL b97fdb57 Nov 11 09:33:09 2016 +0100
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.Dd $Mdocdate: November 30 2016 $
.Dt SSL_CTX_FLUSH_SESSIONS 3
.Os
.Sh NAME
.Nm SSL_CTX_flush_sessions ,
.Nm SSL_flush_sessions
.Nd remove expired sessions
.Sh SYNOPSIS
.In openssl/ssl.h
.Ft void
.Fn SSL_CTX_flush_sessions "SSL_CTX *ctx" "long tm"
.Ft void
.Fn SSL_flush_sessions "SSL_CTX *ctx" "long tm"
.Sh DESCRIPTION
.Fn SSL_CTX_flush_sessions
causes a run through the session cache of
.Fa ctx
to remove sessions expired at time
.Fa tm .
.Pp
.Fn SSL_flush_sessions
is a synonym for
.Fn SSL_CTX_flush_sessions .
.Sh NOTES
If enabled, the internal session cache will collect all sessions established
up to the specified maximum number (see
.Xr SSL_CTX_sess_set_cache_size 3 ) .
As sessions will not be reused once they are expired, they should be
removed from the cache to save resources.
This can either be done automatically whenever 255 new sessions were
established (see
.Xr SSL_CTX_set_session_cache_mode 3 )
or manually by calling
.Fn SSL_CTX_flush_sessions .
.Pp
The parameter
.Fa tm
specifies the time which should be used for the
expiration test, in most cases the actual time given by
.Fn time 0
will be used.
.Pp
.Fn SSL_CTX_flush_sessions
will only check sessions stored in the internal cache.
When a session is found and removed, the
.Va remove_session_cb
is however called to synchronize with the external cache (see
.Xr SSL_CTX_sess_set_get_cb 3 ) .
.Sh RETURN VALUES
.Sh SEE ALSO
.Xr ssl 3 ,
.Xr SSL_CTX_sess_set_get_cb 3 ,
.Xr SSL_CTX_set_session_cache_mode 3 ,
.Xr SSL_CTX_set_timeout 3