add breadcrumb logging to procmgr::run

bootstrap/src/procmgr.rs

@@ -46,15 +46,20 @@ enum VirtualId {
 }
 
 pub fn run(write_fd: FdGuard, socket: Socket, auth: FdGuard, event: FdGuard) -> ! {
+    let _ = libredox::call::write(1, b"PM:0\n");
     // TODO?
     let socket_ident = socket.inner().raw();
+    let _ = libredox::call::write(1, b"PM:1\n");
 
     let queue = RawEventQueue::new(event.as_raw_fd()).expect("failed to create event queue");
+    let _ = libredox::call::write(1, b"PM:2\n");
     drop(event);
+    let _ = libredox::call::write(1, b"PM:3\n");
 
     queue
         .subscribe(socket.inner().raw(), socket_ident, EventFlags::EVENT_READ)
         .expect("failed to listen to scheme socket events");
+    let _ = libredox::call::write(1, b"PM:4\n");
 
     let mut scheme = ProcScheme::new(auth, &queue);
 
@@ -63,6 +68,7 @@ pub fn run(write_fd: FdGuard, socket: Socket, auth: FdGuard, event: FdGuard) ->
     let cap_fd = socket
         .create_this_scheme_fd(0, new_id, 0, 0)
         .expect("failed to issue procmgr root fd");
+    let _ = libredox::call::write(1, b"PM:5\n");
 
     log::debug!("process manager started");
     let _ = syscall::call_wo(