Index: uspace/lib/libc/include/unistd.h
===================================================================
--- uspace/lib/libc/include/unistd.h	(revision 84b14e230361e29caa5996ca93c28c1323646630)
+++ uspace/lib/libc/include/unistd.h	(revision 002252ac07b947d0cd73385616a79aed698567f3)
@@ -51,4 +51,6 @@
 #endif
 
+typedef uint32_t useconds_t;
+
 extern int dup2(int oldfd, int newfd);
 
@@ -68,6 +70,6 @@
 
 extern void _exit(int status) __attribute__ ((noreturn));
-extern int usleep(unsigned long usec);
-extern unsigned int sleep(unsigned int seconds);
+extern int usleep(useconds_t uses);
+extern unsigned int sleep(unsigned int se);
 
 #endif