For some reason file:read_file/1 always returns empty binary when
reading from any file in the "/proc" filesystem.
1> file:read_file("/proc/self/environ").
{ok,<<>>}
2> {ok, FD} = file:open("/proc/self/environ", [read]).
{ok,<0.39.0>}
3> file:read(FD, 1024).
{ok,[82,
69,
77,
...
121|...]}
Serge