- update to 1.9.21:
* Add shell mode to ``jack_control`` (executes commands from stdin until EOF)
* The waf autooption ``--example-tools`` introduced in 1.9.20 is now off by default,
To get the previous behavior back pass ``--example-tools`` during build.
This flag (and the related tools and their code) are going to be removed in the next release.
* Fix alignas() on non-packed architectures
* Fix build of jack-example-tools man pages (1.9.20 regression)
* Fix compatibility with macOS 12
* Fix missing symbols from jack client library (error and info callback pointers)
* Fix potential memory corruption in midi_latency_test tool
* Fix JackWeakAPI on Windows
* Use predefined variables in pkg-config file (required for mingw)