Stdout to stderr redirect option is not working

[saleyn]

When using {stdout, stderr} redirection option, output is printed to screen instead of being delivered to the calling process:

6> f(I), {ok, _, I} = exec:run("echo TEST", [stderr, {stdout, stderr}]).         
{ok,<0.1396.0>,11509}
7> TEST

7> flush().
ok

Workaround: add 1>&2 redirect on command line:

9> f(I), {ok, _, I} = exec:run("echo TEST 1>&2", [stderr]).
{ok,<0.1399.0>,11510}
10> flush().                                                                  
Shell got {stderr,11510,<<"TEST\n">>}
ok

This issue doesn't affect the {stderr, stdout} redirection, which works correctly.

[saleyn]

Fixed in last commit