status code and stderr for %%

[cvogt]

Would be great if %% would return not only the stdout but also stderr and status code. Also, it seems %% is broken in that it terminates commands too early. I tried to use it with tar and ended up with empty or broken archives while % works fine, but writes all output to stdout.

[lihaoyi]

Yeah, I haven't figured out how to make %% capture those other things, but I'm sure it's possible and I want to do it.

I wonder if the early-termination problem is something to do with not fully consuming the output Stream given by %% causing the background process to block and not make progress.

Do you have a nice self-contained repro of the problem I can add to my test suite? That'd make it easier to attack

[cvogt]

regarding the api, how about giving the return value a lazy member stderr for the error stream and a blocking member for the status code. Maybe it would be cleaner to make the stdout a member rather than the return value itself, too, but that may have other api implications I am not aware of. Never used the piping.

[lihaoyi]

yeah seems reasonable. Some kind of structured data would be nice. The whole lazy-vs-strict thing is kinda still in flux; right now most things are strict, so we could make this strict as well and figure out how to make lazy things lazy later if we decide we care

[lihaoyi]

If we end up with something more flexible to deal with the stdout and stderr of the subprocess, we should probably support all the "common" redirect operations, e.g. all those here:

http://tldp.org/HOWTO/Bash-Prog-Intro-HOWTO-3.html

[cvogt]

sounds good. structured data for what?

[lihaoyi]

Structured data so we can access things like the output stream, error stream, exit code, and other things without having to have 100 different %%%%% operators to give us the individual bits we need

[cvogt]

agreed

[lihaoyi]

Fixed by 5d7fb68, will go out in 0.5.1

[cvogt]

awesome :)!