startui: Remove /tmp/launch.sock as root

Fixes #47.
This avoids permission errors.

libos/include/os/LocalServer.h

@@ -136,6 +136,7 @@ namespace os
         ~LocalServer();
 
       private:
+        StringView m_path;
         int m_fd;
         bool m_blocking;
     };

libos/src/LocalServer.cpp

@@ -43,6 +43,7 @@ namespace os
         fcntl(sockfd, F_SETFD, FD_CLOEXEC);
 
         server->m_fd = sockfd;
+        server->m_path = path;
         return server;
     }
 
@@ -63,6 +64,7 @@ namespace os
     LocalServer::~LocalServer()
     {
         close(m_fd);
+        os::FileSystem::remove(m_path);
     }
 
     LocalServer::Client::Client(Client&& other) : m_fd(other.m_fd)

system/startui.cpp

@@ -95,6 +95,8 @@ Result<int> luna_main(int argc, char** argv)
     setsid();
 
     // First of all, start the display server, in case we haven't been started by loginui.
+    // FIXME: What if we're started after a wind process has previously run but exited, so we think there's a wind
+    // process when there isn't.
     if (!os::FileSystem::exists("/tmp/wind.sock"))
     {
         // We need to wait for this one, since its sockets are required later.
@@ -121,6 +123,7 @@ Result<int> luna_main(int argc, char** argv)
     // We also need to wait for this one, since taskbar requires launch.sock.
     bool success = os::IPC::Notifier::run_and_wait(
         [&] {
+            (void)os::FileSystem::remove("/tmp/launch.sock");
             StringView launch_command[] = { "/usr/bin/launch" };
             spawn_process_as_user(Slice<StringView>(launch_command, 1), pw->pw_uid, pw->pw_gid, groups.slice());
         },