/usr/bin/exim4-localscan-plugin-config is in exim4-dev 4.86.2-2ubuntu2.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 | #!/bin/sh
case "$1" in
--localscan-apiversion)
sed -rn 's/#define LOCAL_SCAN_ABI_VERSION_(MAJOR|MINOR) *([0-9]+).*/\2/p' \
/usr/include/exim4/local_scan.h \
| (read MAJOR; read MINOR; echo ${MAJOR}.${MINOR})
;;
*)
echo Usage: $0 --localscan-apiversion
;;
esac
|