status of the hang-on-exit-bug

Michael Stone mstone at
Wed Oct 24 01:32:05 EST 2001

On Tue, Oct 23, 2001 at 04:59:56PM +0200, Markus Friedl wrote:
> openssh's sshd currently tries to do what the rshd does:
> after a SIGCHLD the sshd waits for an EOF from the login shell on
> stdout/stderr. this is because we don't want to loose any data.
> you can avoid this problem by starting the remote command with
> stdin/out/err redirected to /dev/null.
> unlike sshd both telnetd and rlogind exit on SIGCHLD. however, this
> is because they don't care about lost data. but ssh needs to care.
> rlogin does not. this is why ssh hangs and rlogin does not.

what's the rationale for not using the rlogin behavior for interactive
sessions and rsh behavior for non-interactive sessions? (tty/notty)

Mike Stone

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