Index: uspace/lib/c/include/io/log.h
===================================================================
--- uspace/lib/c/include/io/log.h	(revision 9b415c96f2f29f61f5d4f5f7ea3fd3b1ef1ea27a)
+++ uspace/lib/c/include/io/log.h	(revision 3acb285a881a9cf9fc6e09b09a42adaafea9afb3)
@@ -35,4 +35,6 @@
 #define LIBC_IO_LOG_H_
 
+#include <stdarg.h>
+
 typedef enum {
 	LVL_FATAL,
@@ -49,4 +51,5 @@
 extern int log_init(const char *, log_level_t);
 extern void log_msg(log_level_t, const char *, ...);
+extern void log_msgv(log_level_t, const char *, va_list);
 
 #endif