diff --git a/src/lib.rs b/src/lib.rs index 91d76ed..e7b3b51 100644 --- a/src/lib.rs +++ b/src/lib.rs @@ -1063,8 +1063,23 @@ impl fmt::Debug for Command { /// Moves `Fd` out of non-blocking mode. #[cfg(unix)] fn blocking_fd(fd: rustix::fd::BorrowedFd<'_>) -> io::Result<()> { - let flags = rustix::fs::fcntl_getfl(fd)?; - rustix::fs::fcntl_setfl(fd, flags & !rustix::fs::OFlags::NONBLOCK)?; + cfg_if::cfg_if! { + // ioctl(FIONBIO) sets the flag atomically, but we use this only on Linux + // for now, as with the standard library, because it seems to behave + // differently depending on the platform. + // https://github.com/rust-lang/rust/commit/efeb42be2837842d1beb47b51bb693c7474aba3d + // https://github.com/libuv/libuv/blob/e9d91fccfc3e5ff772d5da90e1c4a24061198ca0/src/unix/poll.c#L78-L80 + // https://github.com/tokio-rs/mio/commit/0db49f6d5caf54b12176821363d154384357e70a + if #[cfg(target_os = "linux")] { + rustix::io::ioctl_fionbio(fd, false)?; + } else { + let previous = rustix::fs::fcntl_getfl(fd)?; + let new = previous & !rustix::fs::OFlags::NONBLOCK; + if new != previous { + rustix::fs::fcntl_setfl(fd, new)?; + } + } + } Ok(()) }