When fossil start editor (or diff) application, it use 'system(...)' function and mingw(msvcrt) runtime interprets it to <code>getenv("COMSPEC") + " /c " + "..."</code>.<br>So if environment variable 'COMSPEC' set to "...\cmd.exe", editor name depends on "cmd.exe"'s quoting rule and application search rule.<br>&gt; <tt>fossil set editor <tt>fossil set editor<br>editor (local) "C:\Program