--- src/oss4/oss.h.orig	2015-05-31 03:28:37.000000000 +0500
+++ src/oss4/oss.h	2015-10-18 17:07:53.035019000 +0500
@@ -27,6 +27,9 @@
 #include <string.h>
 #include <sys/ioctl.h>
 
+#include <poll.h>
+#include <pthread.h>
+
 #ifdef HAVE_SYS_SOUNDCARD_H
 #include <sys/soundcard.h>
 #else
@@ -141,6 +144,9 @@
 
     bool m_paused = false;
     bool m_ioctl_vol = false;
+
+    pthread_mutex_t m_mutex = PTHREAD_MUTEX_INITIALIZER;
+    pthread_cond_t m_cond = PTHREAD_COND_INITIALIZER;
 };
 
 /* utils.c */