Build the current document and rebuild it as input files change.
tectonic -X watch [--exec COMMAND] [-x COMMAND]
This command builds the current document in the same fashion as
tectonic -X build, and then stays running and watches for changes to the input
files. It rebuilds the document when changes are detected.
--exec option (or
-x for short) configures the command that is used to
run the document build. The value of this option is appended to
and defaults to
build. If you want to pass options to the build command, this
is the way to do so.