diff --git a/sysdeps/unix/sysv/sco3.2.4/sigaction.h b/sysdeps/unix/sysv/sco3.2.4/sigaction.h
new file mode 100644
index 0000000000..c6344f0810
--- /dev/null
+++ b/sysdeps/unix/sysv/sco3.2.4/sigaction.h
@@ -0,0 +1,39 @@
+/* The proper definitions for SCO's sigaction.
+Copyright (C) 1993, 1994 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU 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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the, 1992 Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+/* Structure describing the action to be taken when a signal arrives.  */
+struct sigaction
+  {
+    /* Signal handler.  */
+    __sighandler_t sa_handler;
+
+    /* Additional set of signals to be blocked.  */
+    __sigset_t sa_mask;
+
+    /* Special flags.  */
+    int sa_flags;
+  };
+
+/* Bits in `sa_flags'.  */
+#define	SA_NOCLDSTOP	0x01	/* Don't send SIGCHLD when children stop.  */
+
+/* Values for the HOW argument to `sigprocmask'.  */
+#define	SIG_SETMASK	0	/* Set the set of blocked signals.  */
+#define	SIG_BLOCK	1	/* Block signals.  */
+#define	SIG_UNBLOCK	2	/* Unblock signals.  */