In ssh_config.d, the file 9999999gentoo.conf contains (exclusively) SendEnv instructions. If a user adds their config into say 123-config.conf, as is intended, then those SendEnv lines will get applied afterwards. As opposed to most instructions in ssh_config, SendEnv is not "first come first serve", later occurrences are merged into earlier ones. To quote the man page: > Multiple environment variables may be separated by > whitespace or spread across multiple SendEnv directives. > [...] > It is possible to clear previously set SendEnv variable > names by prefixing patterns with -. The default is not to > send any environment variables." 9999999gentoo.conf contains "SendEnv LANG LC_ALL [...]", so if I want to not send LC_ALL, I can do so using "SendEnv -LC_ALL". However I have to put that line *after* "SendEnv LC_ALL", or else the latter will overwrite it and send it anyway. As such, there is no way to stop LC_ALL and the other variables mentioned in 9999999gentoo.conf from being sent using my 123-config.conf, I would have to create a second configuration file zzz-config.conf, in which I then could not overwrite other directives set in for example 9999999gentoo-security.conf I propose to move SendEnv instructions to 0000000gentoo.conf Further, even that would still not allow a user to not send LC_ALL by setting "SendEnv -LC_ALL" in their ~/.ssh/config, a possible solution might be to import that file a second time after the 0000000gentoo.conf file, say in 0000001gentoo.conf
