4.19 Issues with Cygwin ssh

This section is incomplete. Please share your solutions.

Cygwin’s ssh works only with a Cygwin version of Emacs. To check for compatibility: type M-x eshell, and start ssh test.host. Incompatibilities trigger this message:

Pseudo-terminal will not be allocated because stdin is not a terminal.

Some older versions of Cygwin’s ssh work with the sshx access method. Consult Cygwin’s FAQ at http://cygwin.com/faq/ for details.

When using the scpx access method, Emacs may call scp with Windows file naming, such as c:/foo. But the version of scp that is installed with Cygwin does not know about Windows file naming, which causes it to incorrectly look for a host named c.

A workaround: write a wrapper script for scp to convert Windows file names to Cygwin file names.

When using the ssh-agent on Windows for password-less interaction, ssh methods depend on the environment variable SSH_AUTH_SOCK. But this variable is not set when Emacs is started from a Desktop shortcut and authentication fails.

One workaround is to use a Windows based SSH Agent, such as Pageant. It is part of the Putty Suite of tools.

The fallback is to start Emacs from a shell.