Overriding the default args parameter in the spec

[mikebrow]

With the current spec command the args parameter defaults to sh. This works well for containers that include the sh command, but not so well for other containers.

One has to edit the config.json just to run hello-world. Examples:
sed -i 's;"sh";"/hello";' config.json
sed -i 's/"sh"/"echo","-n","hi"/' config.json
edit args using a text editor.

For usability sake... I recommend we either add an optional --args parameter to the runc spec command, or the runc start command (or both) to enable overriding the default arg array; or we document using sed in the usage for the spec and start commands. I prefer adding --args parameters.

Thoughts? I'll put a PR together for it.

Cheers, Mike

[marcosnils]

The runC readme states:

It assumes that the file-system is found in a directory called rootfs and there is a user with uid and gid of 0 defined within that file-system.

Maybe adding that it assumes that the rootfs has sh is enough?

[crosbymichael]

The specs commands just creates an example config as a starting point for you to build on.

its just meant as a starting point, thats all.

[mikebrow]

I'll update the usage for spec/start to reflect that. This to reduce the possible number of incoming reported issues and questions. Cheers.