Launching ssh without a tty

On receipt of a specially coded email, I want to launch ssh to set up a vpn with a remote host. In my sendmail (8.10 I think) aliases file, I've got an alias like "|/users/me/vpn 2>&1 >>/tmp/vpn.out", and I've created a shell script /user/me/vpn which does

ssh -v -f -N -n -l leriche.p -R 8099:localhost:99 $ipaddr

If I su - to daemon (which sendmail uses to execute commands to pipe mail through) and then run my script from the command line, it works just fine, showing that it can find the necessary keys, but when I send mail to the alias, nothing seems to happen. Not even any verbose output to /tmp/vpn.out.

I thought the -N and/or the -N would allow ssh to work in this environment, but apparently not. Any ideas?

• Philip --

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  Philip Le Riche Voice: +44 1442 884390 (Ouaithe qu'i' sait L'Riche, chu Fax: +44 1442 884943 pouôrre baloque né pâle pon l'Jèrriais) Email: pleriche@altair.steria.co.uk

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