know the filename of the -f argument, it should be possible to
include "./" relative to it.

The footnote is that the include is resolved at lower privlevel
than the -f file is read, so in really obscure cases you could
have really obscure error messages.

VCL file, and illegal everywhere else.

This makes it easier to distribute "VCL-packages"

Test-case written by:	Kacper

the VCL fileopening logic in mgt so we have it only one place.

away const.

for more clarity, before we start hacking VCC further.

all other methods use rdlock

Submitted by:	github::onovy

In the 304 case we were already skipping it for non-zero C-L.
For 204 responses this was introduced as a side effect of 271e1c52.

Fixes:	#1823

for 5 seconds if there is a waiting list.

This allows the waiting list to drain (returning 503) quickly,
rather than one by one trying to pester the backend and only
giving up after the connect_timeout.

Related to: #1823

new improved probability of getting the VSL out.

That obscured problems in cleanup

The script lacked a logexpect -wait at the end telling it to actually
wait for the required log content.

Added a new rule to match first on an actual retry backend transaction
and match the header set/unset/set tests on that vxid.

Check if system has closefrom(2) and use that where available

represents the current limit.

Also don't call it every iteration of the loop.

Avoids memcpy/free if the buffer was dynamic.