If memfile_buffer_count != 0, first messages are lost

[KerstinKeller]

Problem Description

With a higher memfile_buffer_count, not all messages reach the subscriber, see the testcase in this commit:
master...hotfix/shm-buffer-count-testcase

How to reproduce

Run the provided testcase.

How did you get eCAL?

I don't know

Environment

Current master

eCAL System Information

No response

[chengguizi]

Any update on this so far? Not sure how this would be affected by the major zero-copy change in #1082

Having a circular buffer of memfiles + zero copy would be a really great feature to have for low-latency, high-frequency, low-drop message system.

[rex-schilasky]

@chengguizi this fix is in progress and will be part of 5.12.

[chengguizi]

Sounds good! Very look forward to an improved zero-copy implementation that also supports circular buffer (hence avoid missing messages) :)