Index: uspace/lib/posix/include/posix/unistd.h
===================================================================
--- uspace/lib/posix/include/posix/unistd.h	(revision ee5913cb8f3d028216e39b7fb69b86747659d7eb)
+++ uspace/lib/posix/include/posix/unistd.h	(revision 5759642fc10d592323e48fdc42f5ca4046946fd0)
@@ -146,4 +146,6 @@
 extern int __POSIX_DEF__(pipe)(int fildes[2]);
 
+/* Issue alarm signal. */
+extern unsigned int __POSIX_DEF__(alarm)(unsigned int);
 
 #endif /* POSIX_UNISTD_H_ */
Index: uspace/lib/posix/source/unistd.c
===================================================================
--- uspace/lib/posix/source/unistd.c	(revision ee5913cb8f3d028216e39b7fb69b86747659d7eb)
+++ uspace/lib/posix/source/unistd.c	(revision 5759642fc10d592323e48fdc42f5ca4046946fd0)
@@ -422,4 +422,10 @@
 }
 
+unsigned int posix_alarm(unsigned int seconds)
+{
+	not_implemented();
+	return 0;
+}
+
 /** @}
  */