Carbon's entrypoint puts LD_PRELOAD=libdoorstop.so in front of the whole
startup string, and with Carbon's DOORSTOP_* environment that preloader
breaks the launcher shell's own command substitution: the sidecar's
--print-config output went straight to the console and the capture came
back empty. The first Carbon server built from the egg printed its config
JSON, token included, unframed, then "server id 'main', sidecar URL
http://192.168.0.12: (listening on )" and never the once-only banner.
`env -u LD_PRELOAD` on the sidecar alone was not enough: the shell doing
the capturing had the preload too.
The launcher now re-execs itself once without LD_PRELOAD, keeps it aside,
and gives it back to the game in run_game, the only process that needs it.
Reproduced and fixed under Carbon's real environment (environment.sh +
libdoorstop.so): the released launcher dumps the JSON; this one prints the
banner and "server id 'egg-carbon', sidecar URL http://192.168.0.12:21019",
and the game still gets LD_PRELOAD and DOORSTOP_ENABLED. The four
no-preload cases in the game image are unchanged.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E14m6SuuY6i1vASFeGDBeY
