From 93e9a42bf04a1ec841353e7b1959107c731d60ad Mon Sep 17 00:00:00 2001
From: Andreas Kling <awesomekling@gmail.com>
Date: Fri, 3 Jan 2020 03:36:17 +0100
Subject: [PATCH] test_io: Verify that write() on an O_RDONLY fd fails with
 EBADF

---
 Userland/test_io.cpp | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/Userland/test_io.cpp b/Userland/test_io.cpp
index 043fc2360dd..2296dff418a 100644
--- a/Userland/test_io.cpp
+++ b/Userland/test_io.cpp
@@ -64,6 +64,17 @@ void test_read_from_writeonly()
     ASSERT(rc == 0);
 }
 
+void test_write_to_readonly()
+{
+    char str[] = "hello";
+    int fd = open("/tmp/abcd123", O_CREAT | O_RDONLY);
+    ASSERT(fd >= 0);
+    int rc;
+    EXPECT_ERROR_3(EBADF, write, fd, str, sizeof(str));
+    rc = close(fd);
+    ASSERT(rc == 0);
+}
+
 int main(int, char**)
 {
     int rc;
@@ -78,6 +89,7 @@ int main(int, char**)
     test_read_from_directory();
     test_write_to_directory();
     test_read_from_writeonly();
+    test_write_to_readonly();
 
     return 0;
 }