Feat: WIP terse code documentation

src/main.rs

@@ -56,7 +56,26 @@ struct Args {
     buffer: Option<u32>,
 }
 
+#[cfg(unix)]
+fn redirect_stderr() -> Option<std::fs::File> {
+    use std::os::fd::FromRawFd;
+
+    let mut fds = [0i32; 2];
+    if unsafe { libc::pipe(fds.as_mut_ptr()) } != 0 {
+        return None;
+    }
+    unsafe {
+        libc::dup2(fds[1], libc::STDERR_FILENO);
+        libc::close(fds[1]);
+        libc::fcntl(fds[0], libc::F_SETFL, libc::O_NONBLOCK);
+        Some(std::fs::File::from_raw_fd(fds[0]))
+    }
+}
+
 fn main() -> io::Result<()> {
+    #[cfg(unix)]
+    let mut stderr_pipe = redirect_stderr();
+
     #[cfg(unix)]
     engine::realtime::lock_memory();
 
@@ -171,6 +190,26 @@ fn main() -> io::Result<()> {
             app.ui.flash(&err, 3000, state::FlashKind::Error);
         }
 
+        #[cfg(unix)]
+        if let Some(ref mut pipe) = stderr_pipe {
+            use std::io::Read;
+            let max_len = terminal.size().map(|s| s.width as usize).unwrap_or(80).saturating_sub(16);
+            let mut buf = [0u8; 1024];
+            while let Ok(n) = pipe.read(&mut buf) {
+                if n == 0 {
+                    break;
+                }
+                let text = String::from_utf8_lossy(&buf[..n]);
+                for line in text.lines() {
+                    let line = line.trim();
+                    if !line.is_empty() {
+                        let capped = if line.len() > max_len { &line[..max_len] } else { line };
+                        app.ui.flash(capped, 5000, state::FlashKind::Error);
+                    }
+                }
+            }
+        }
+
         app.playback.playing = playing.load(Ordering::Relaxed);
 
         while let Ok(midi_cmd) = midi_rx.try_recv() {