postinst is in golang-1.10-go 1.10.1-1ubuntu2.
This file is a maintainer script. It is executed when installing (*inst) or removing (*rm) the package.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 | #!/bin/sh
set -e
case "$1" in
configure)
# Very ugly hack to set timestamps same as /usr/lib/go-1.10/bin/go
find /usr/lib/go-1.10/pkg -exec touch -r /usr/lib/go-1.10/bin/go {} \;
;;
*)
;;
esac
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