So, I finally took the time to use process monitor (sysinternals.com). I provided the logging in a pull request to a pull request to openssh-portable: https://github.com/manojampalam/openssh-portable/pull/2 The short of it is that CreateProcessW decides how to find a program in a command string based on a heuristic. ssh uses `'` instead of `"` because it's guarding something (expansion of hostnames I think). Under this condition, Windows decided that either the entire string was a complete path to a program or it was a complete path to a program without ".exe". If the first character of the command is a `"`, and there's a matching `"`, CreateProcessW will use that as its starting point for finding the program. Otherwise, if a `"` character is introduced into the command-line somewhere else, Windows knows that nothing past that can possibly be part of the program path - as ideally people would stick the program path in `"` too. The current PR to openssh-portable replaces the `'` with `"` which enables CreateProcessW to search backwards from that point, trying each thing up to a ` ` to see "are you a program?"/"are you a program if I add .exe?" Which is still pretty inefficient. Ideally one can tell CreateProcessW "this is the program". I sent a naïve PR which just helps CreateProcessW along and then the more correct one which tells it "this is it". I don't think openssh itself needs to use `'` as opposed to `"` for the proxy jump. And I'm pretty sure it could tolerate the quotes around the program itself. _______________________________________________ openssh-unix-dev mailing list openssh-unix-dev@xxxxxxxxxxx https://lists.mindrot.org/mailman/listinfo/openssh-unix-dev
