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.