auto import from //depot/cupcake/@135843
diff --git a/libc/unistd/alarm.c b/libc/unistd/alarm.c
new file mode 100644
index 0000000..01863a4
--- /dev/null
+++ b/libc/unistd/alarm.c
@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) 1983, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#if defined(LIBC_SCCS) && !defined(lint)
+static char sccsid[] = "@(#)alarm.c 8.1 (Berkeley) 6/4/93";
+#endif /* LIBC_SCCS and not lint */
+#include <sys/cdefs.h>
+//__FBSDID("$FreeBSD: /repoman/r/ncvs/src/lib/libc/gen/alarm.c,v 1.3 2007/01/09 00:27:53 imp Exp $");
+
+/*
+ * Backwards compatible alarm.
+ */
+#include <sys/time.h>
+#include <unistd.h>
+
+unsigned int
+alarm(secs)
+ unsigned int secs;
+{
+ struct itimerval it, oitv;
+ struct itimerval *itp = ⁢
+
+ itp->it_interval.tv_usec = 0;
+ itp->it_interval.tv_sec = 0;
+ itp->it_value.tv_sec = secs;
+ itp->it_value.tv_usec = 0;
+ if (setitimer(ITIMER_REAL, itp, &oitv) < 0)
+ return (-1);
+ if (oitv.it_value.tv_usec)
+ oitv.it_value.tv_sec++;
+ return (oitv.it_value.tv_sec);
+}