function
/usr/local/lib/janet/spork/sh.janet on line 37 , column 1
(exec-slurp-all & args )
It executes args with `os/spawn` and returns a struct which has the
following keys.
* `:out` - trimmed standard output of the process
* `:err` - trimmed standard error of the process
* `:status` - the exit code of the process
Before the function finishes , the spawned process is closed for
resource control.