system calls and threading question

[Samuel Rivas]

Yariv Sadan wrote:
> I have a question about how Erlang handles system calls: what effect
> (if any) does a function call that leads to system call invocation
> (e.g. os:cmd) have on the scheduler? Do such system calls block the
> entire BEAM process (and hence all lightweight Erlang processes) or
> are they handled in a separate system thread (or thread pool), such
> that other lightweight processes are not blocked?
 
  os:cmd does not make system calls itself; it creates a port, so the
system call is invoked in a separate os thread (that is, outside the
erlang runtime).

Regards
-- 
	Samuel