/usr/share/std_srvs/srv/Trigger.srv is in libstd-srvs-dev 1.11.1-3.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 | ---
bool success # indicate successful run of triggered service
string message # informational, e.g. for error messages
|