system calls and threading question

[Matthias Lang]

Yariv Sadan writes:

 > 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

You can verify for yourself that work done in os:cmd does _not_ tie up
the entire erlang node:

1> spawn(fun() -> os:cmd("sleep 1000") end).
<0.42.0>
2> 3 + 4.
7

Matthias