[CM] How to capture standard output of Linux command in s7

[bil at ccrma.Stanford.EDU]

> system prints the  output of the command.
> I cannot save the output with:
> (define sv (system ("ls"))

That's what the #t argument did in the example I gave,
as mentioned in the help string.

repl
<1> (define sv (system "ls -la s7.c" #t))
"-rw-------  1 bil  staff  2274682 Nov 24 10:36 s7.c
"
<2> sv
"-rw-------  1 bil  staff  2274682 Nov 24 10:36 s7.c
"