DTLSv1_get_timeout(3)

DTLSv1_get_timeout(3) | OpenSSL | DTLSv1_get_timeout(3)

# NAME

DTLSv1_get_timeout - determine when a DTLS or QUIC SSL object next needs a timeout event to be handled

# SYNOPSIS

     #include <openssl/ssl.h>
     int DTLSv1_get_timeout(SSL *s, struct timeval *tv);

# DESCRIPTION

DTLSv1_get_timeout() can be used on a DTLS or QUIC SSL object to determine when the SSL object next needs to perform internal processing due to the passage of time.

Calling DTLSv1_get_timeout() results in *tv being written with an amount of time left before the SSL object needs have DTLSv1_handle_timeout() called on it. If the SSL object needs to be ticked immediately, *tv is zeroed and the function succeeds, returning 1. If no timeout is currently active, this function returns 0.

This function is only applicable to DTLS and QUIC objects. It fails if called on any other kind of SSL object.

Note that the value output by a call to DTLSv1_get_timeout() may change as a result of other calls to the SSL object.

Once the timeout expires, DTLSv1_handle_timeout() should be called to handle any internal processing which is due; for more information, see DTLSv1_handle_timeout(3).

SSL_get_event_timeout(3) supersedes all use cases for this this function and may be used instead of it.

# RETURN VALUES

On success, writes a duration to *tv and returns 1.

Returns 0 on failure, or if no timeout is currently active.

# SEE ALSO

DTLSv1_handle_timeout(3), SSL_get_event_timeout(3), ssl(7)

# COPYRIGHT

Copyright 2023 The OpenSSL Project Authors. All Rights Reserved.

Licensed under the Apache License 2.0 (the "License"). You may not use this file except in compliance with the License. You can obtain a copy in the file LICENSE in the source distribution or at <https://www.openssl.org/source/license.html>.

2025-07-01 | 3.5.1