Fix breakage in maint/build-mdbook
Currently, the build-mdbook script gives an error and fails with:
2024-08-21 08:06:48 [INFO] (mdbook::renderer): Invoking the "null" renderer
2024-08-21 08:06:48 [WARN] (mdbook::renderer): Error writing the RenderContext to the backend, Broken pipe (os error 32)
That's because, for our dummy renderer, we use "true". But apparently this causes a failure, since "true" exits before its stdin is closed, which now causes mdbook to complain.
We can't set the command to cat >/dev/null
, since the "command"
apparently has to be a single executable.
So, out of all of the mandatory POSIX commands that (when run
without arguments) consume stdin and return true, the best choice
seemed to be using wc
, which only outputs a single line.
One alternative would have been adding a "cat_dev_null" script, and making sure that it was in the path, but that seemed excessive.