test for write_append from Andy Shevchenko

regress/sys/kern/write_append/Makefile

@@ -0,0 +1,15 @@
+#	$NetBSD: Makefile,v 1.1 2008/08/27 06:40:13 christos Exp $
+
+NOMAN=		# defined
+
+PROG=		write_append
+WARNS?=		4
+
+regress:
+	@if ${.OBJDIR}/${PROG} 2> /dev/null; then \
+		echo "PASSED"; \
+	else \
+		echo "FAILED"; \
+	fi
+
+.include <bsd.prog.mk>

regress/sys/kern/write_append/write_append.c

@@ -0,0 +1,34 @@
+#include <err.h>
+#include <unistd.h>
+#include <fcntl.h>
+
+static const char fn[] = "/tmp/write-test.txt";
+static const char str[] = "Test write() append\n";
+static size_t len = sizeof(str) - 1;
+
+int
+main(void)
+{
+	int fd;
+	off_t off;
+
+	if ((fd = open(fn, O_CREAT | O_RDWR, 0600)) == -1)
+		err(1, "Cannot open `%s'", fn);
+	if (write(fd, str, len) != (ssize_t)len)
+		err(1, "Write failed");
+	if (close(fd) == -1)
+		err(1, "Close failed");
+	if ((fd = open(fn, O_WRONLY | O_APPEND)) == -1)
+		err(1, "Cannot open `%s'", fn);
+        if ((off = lseek(fd, (off_t) 0, SEEK_SET)) != (off_t)0)
+		err(1, "Seek failed");
+	if (write(fd, str, 0) != 0)
+		err(1, "Write failed");
+        if ((off = lseek(fd, (off_t) 0, SEEK_CUR)) != (off_t)0)
+		errx(1, "bad seek offset %lld\n", (long long)off);
+	if (close(fd) == -1)
+		err(1, "Close failed");
+	if (unlink(fn) == -1)
+		err(1, "Unlink failed");
+	return 0;
+}