diff --git a/sysdeps/unix/sysv/sysv4/sigaction.h b/sysdeps/unix/sysv/sysv4/sigaction.h
new file mode 100644
index 0000000000..d2a236463a
--- /dev/null
+++ b/sysdeps/unix/sysv/sysv4/sigaction.h
@@ -0,0 +1,54 @@
+/* Copyright (C) 1991, 1992, 1993 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.  */
+
+/* The proper definitions for SVR4's sigaction.
+   If the operating system has a `sigaction' system call that correctly
+   implements the POSIX.1 behavior, there should be a system-dependent
+   version of this file that defines `struct sigaction' and the `SA_*'
+   constants appropriately.  */
+
+/* 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;
+
+    /* Padding.  */
+    int sa_resv[2];
+  };
+
+/* Bits in `sa_flags'.  */
+#define	SA_ONSTACK	0x1	/* Take signal on signal stack.  */
+#define SA_RESETHAND	0x2	/* Reset to SIG_DFL on entry to handler.  */
+#define	SA_RESTART	0x4	/* Don't restart syscall on signal return.  */
+#define SA_SIGINFO	0x8	/* Provide additional info to the handler.  */
+#define SA_NODEFER	0x10	/* Don't automatically block the signal when
+ 				   its handler is being executed.  */
+#define SA_NOSCLDWAIT	0x10000	/* Don't create zombie processes.  */
+#define	SA_NOCLDSTOP	0x20000	/* Don't send SIGCHLD when children stop.  */
+
+/* Values for the HOW argument to `sigprocmask'.  */
+#define	SIG_BLOCK	1	/* Block signals.  */
+#define	SIG_UNBLOCK	2	/* Unblock signals.  */
+#define	SIG_SETMASK	3	/* Set the set of blocked signals.  */