diff --git a/libc/Makefile b/libc/Makefile
index ece8baa4..445ab2d8 100644
--- a/libc/Makefile
+++ b/libc/Makefile
@@ -312,6 +312,7 @@ SIG_DFL.o \
SIG_ERR.o \
SIG_IGN.o \
signal.o \
+sigprocmask.o \
sleep.o \
stat.o \
stdio.o \
diff --git a/libc/sigprocmask.cpp b/libc/sigprocmask.cpp
new file mode 100644
index 00000000..33407499
--- /dev/null
+++ b/libc/sigprocmask.cpp
@@ -0,0 +1,34 @@
+/*******************************************************************************
+
+ Copyright(C) Jonas 'Sortie' Termansen 2013.
+
+ This file is part of the Sortix C Library.
+
+ The Sortix C Library is free software: you can redistribute it and/or modify
+ it under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or (at your
+ option) any later version.
+
+ The Sortix C Library is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
+ License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with the Sortix C Library. If not, see .
+
+ sigprocmask.cpp
+ Examine and change blocked signals.
+
+*******************************************************************************/
+
+#include
+#include
+
+extern "C" int sigprocmask(int how, const sigset_t* set, sigset_t* oldset)
+{
+ (void) how;
+ (void) set;
+ (void) oldset;
+ return 0;
+}