start-process to run mplayer and when playing videos I get a ton of output to stderr from "vdp_...". On the command line I usually just 2>/dev/null but
start-process runs it directly without a shell. (I tried
start-process-shell-command but it simply does not work at all).
call-process lets you provide a list for separate stdout and stderr but it seems
start-process does not. I don't see an option to mplayer to inhibit the output. If only there were a way to do with
start-process what you can do with
call-process. Is there some way I'm not seeing to do this?
Emacs 25 introduced the function
make-process for creating asynchronous processes, which is lower-level than
start-process. In particular, you can separate
stdout by passing a buffer or pipe as the function's
:stderr keyword argument.
See the Emacs Lisp Manual node on Asynchronous Processes for more information.