Build a virtual device to output events

src/main.rs

@@ -1,18 +1,29 @@
 use std::error::Error;
+use evdev::{Device, EventType};
 
 mod input;
 mod select;
+mod output;
 
-fn main() -> Result<(), Box<dyn Error>> {
-    let mut device = input::select_device();
-    device.grab()?;
+fn event_loop(input_device: &mut Device) -> Result<(), Box<dyn Error>> {
+    let mut output_device = output::build_device().unwrap();
     for _ in 0..5 {
-        if select::is_readable(&mut device) {
-            for ev in device.fetch_events().unwrap() {
-                println!("event: {:?}", ev);
+        if !select::is_readable(input_device) { continue }
+
+        for event in input_device.fetch_events().unwrap() {
+            if event.event_type() == EventType::KEY {
+                println!("event: {:?}", event);
             }
+            output_device.emit(&[event]).unwrap();
         }
     }
+    Ok(())
+}
+
+fn main() -> Result<(), Box<dyn Error>> {
+    let mut device = input::select_device();
+    device.grab()?;
+    event_loop(&mut device)?;
     device.ungrab()?;
     Ok(())
 }

src/output.rs

@@ -0,0 +1,16 @@
+use std::error::Error;
+use evdev::{AttributeSet, Key};
+use evdev::uinput::{VirtualDevice, VirtualDeviceBuilder};
+
+pub fn build_device() -> Result<VirtualDevice, Box<dyn Error>> {
+    let mut keys = AttributeSet::<Key>::new();
+    keys.insert(Key::KEY_A);
+
+    let device = VirtualDeviceBuilder::new()?
+        .name("xremap")
+        .with_keys(&keys)?
+        .build()
+        .unwrap();
+
+    Ok(device)
+}