Add a test that fails if `#[unix_sigpipe = "inherit"]` wrongly results in `SIGPIPE` being `SIG_DFL` if the parent has `SIG_IGN`. We have no current test for this particular case.
Add a test that fails if `#[unix_sigpipe = "inherit"]` wrongly results in `SIGPIPE` being `SIG_DFL` if the parent has `SIG_IGN`. We have no current test for this particular case.