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$ABI strict
$Module h2 3 "Module to control the built-in HTTP2 transport"

DESCRIPTION
===========

This VMOD contains functions to control the HTTP2 transport built into
Vinyl Cache.

$Function BOOL is()
$Restrict client

Returns true when called on a session handled by the built-in HTTP2 transport.

$Function DURATION rapid_reset([DURATION threshold])
$Restrict client

Get and optionally set the ``h2_rapid_reset`` parameter (See
:ref:`vinyld(1)`) for this HTTP2 session only.

Returns -1 when used outside the HTTP2 transport. Otherwise returns
the previous value.

If the call leads to a change in the rate limit parameters, the
current budget as retuned by
`h2.rapid_reset_budget()`_ is reset.

$Function INT rapid_reset_limit([INT number])
$Restrict client

Get and optionally set the ``h2_rapid_reset_limit`` parameter (See
:ref:`vinyld(1)`) for this HTTP2 session only.

Returns -1 when used outside the HTTP2 transport. Otherwise returns
the previous value.

If the call leads to a change in the rate limit parameters, the
current budget as retuned by
`h2.rapid_reset_budget()`_ is reset.

$Function DURATION rapid_reset_period([DURATION duration])
$Restrict client

Get and optionally set the ``h2_rapid_reset_period`` parameter (See
:ref:`vinyld(1)`) for this HTTP2 session only.

Returns -1 when used outside the HTTP2 transport. Otherwise returns
the previous value.

If the call leads to a change in the rate limit parameters, the
current budget as retuned by
`h2.rapid_reset_budget()`_ is reset.

$Function REAL rapid_reset_budget()
$Restrict client

Return how many RST frames classified as "rapid" the client is still
allowed to send before the session is going to be closed.

SEE ALSO
========

* :ref:`vinyld(1)`
* :ref:`vsl(7)`
