Bernstein chained ssh-add

Rationale

Ssh-agent already allows Bernstein chained form, but ssh-add, for some reason, doesn't. Thus, it's not possible to do the following:

ssh-agent ssh-add path/to/key git push

Instead you have to resort to clumsier ways. For example:

ssh-agent bash -c 'ssh-add path/to/key; git push'

This utility makes Bernstein chained ssh-add possible:

ssh-agent ssh-added path/to/key git push

In fact, this is almost exactly how this repository was pushed to GitHub.

This utility is not complicated, it's only a couple of lines of code. Another example:

ssh-agent ssh-added path/to/key echo Hello, world

This utility also uses -q flag with ssh-add to suppress noise.

Installation

Copy ssh-added script somewhere in your path.

License

MIT.

Dependencies

As of author's knowledge, only POSIX and ssh-add.

References

Bernstein chaining: https://en.wikipedia.org/wiki/Chain_loading.

Example of Bernstein chaining: https://skarnet.org/software/execline/grammar.html.

More on Bernstein chaining: https://www.catb.org/~esr/writings/taoup/html/ch06s06.html.