Add support or documentation for "timestamp_timeout = 0" scenario

[yuriybabenko]

Have been struggling with getting sudo-prompt to work, and finally figured out why. My environment's timestamp timeout was set to 0. This resulted in attempt()'s check of the if (/sudo: /i.test(stderr)) condition always matching, and throwing an error on the second command execution.

It would be nice if there was either a) a workaround, or b) a check for this condition within sudo-prompt and subsequent user notification.

[jorangreef]

Are you on OS X?

Are you getting User did not grant permission. as an error message?

Would you be able to find out if there is any way to detect whether the sudo timestamp timeout is 0? If so, we could fall back to another version of attempt() which does not assume that timeouts on OS X are non-zero, and which will run the command directly as part of the AppleScript applet, which is normally used to extend the sudo timestamp. Would you be able to help with this?

[yuriybabenko]

Yes, I'm on OSX 10.10.4.

I looked around and I'm not seeing a way to check the current sudo timeout. The value is set in /etc/sudoers, but you need sudo permissions to actually read the file, so it can't be parsed.

It may be possible to tell sudo to use sudo-prompt's applet.app as the GUI for ASKPASS. Alternatively, these two resources seem to be on the right track:

• http://apple.stackexchange.com/a/23514/71676
• https://github.com/markcarver/mac-ssh-askpass

Will investigate this further when I have more time.

[jorangreef]

I have been thinking about it some more. I will try to rewire attempt() so that it does not assume that sudo timeouts are non-zero. Instead it will:

1. Try sudo -n to run the command if possible (if a sudo session already exists).
2. Use the applet's administrator privileges to set the timeout as well as run the provided command.

This will give the best of both worlds. A sudo session which endures across multiple commands if possible, and support for systems with the sudo timeout set to 0.

It will take me some time but I hope to get started on it soon.