diff --git a/CHANGES.md b/CHANGES.md
index 8ba5a42639..d347f12625 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -11,6 +11,7 @@ Features
 * [#1544](https://github.com/java-native-access/jna/pull/1544): Add `GetPriorityClass`, `SetPriorityClass`, `GetThreadPriority`, `SetThreadPriority` and associated constants to `c.s.j.p.win32.Kernel32` - [@dEajL3kA](https://github.com/dEajL3kA).
 * [#1548](https://github.com/java-native-access/jna/pull/1548): Make interface `c.s.j.p.mac.XAttr public` - [@matthiasblaesing](https://github.com/matthiasblaesing).
 * [#1551](https://github.com/java-native-access/jna/pull/1551): Add `c.s.j.p.bsd.ExtAttr` and `c.s.j.p.bsd.ExtAttrUtil` to wrap BSD [<sys/extattr.h>](https://man.freebsd.org/cgi/man.cgi?query=extattr&sektion=2) system calls. [@rednoah](https://github.com/rednoah).
+* [#1517](https://github.com/java-native-access/jna/pull/1517): Add missing `O_*` (e.g. `O_APPEND`, `O_SYNC`, `O_DIRECT`, ...) to `c.s.j.p.linux.Fcntl` - [@matthiasblaesing](https://github.com/matthiasblaesing).
 
 Bug Fixes
 ---------
diff --git a/contrib/platform/src/com/sun/jna/platform/linux/Fcntl.java b/contrib/platform/src/com/sun/jna/platform/linux/Fcntl.java
index c5afe0dd5a..d99099fe60 100644
--- a/contrib/platform/src/com/sun/jna/platform/linux/Fcntl.java
+++ b/contrib/platform/src/com/sun/jna/platform/linux/Fcntl.java
@@ -38,9 +38,26 @@ public interface Fcntl {
      * Bits OR'd into the second argument to open. Note these are defined
      * differently on linux than unix fcntl header
      */
-    int O_CREAT = 0100; // Create file if it doesn't exist.
-    int O_EXCL = 0200; // Fail if file already exists.
-    int O_TRUNC = 01000; // Truncate file to zero length.
+    int O_CREAT     = 000000100; // Create file if it doesn't exist.
+    int O_EXCL      = 000000200; // Fail if file already exists.
+    int O_TRUNC     = 000001000; // Truncate file to zero length.
+    int O_APPEND    = 000002000;
+    int O_NONBLOCK  = 000004000;
+    int O_DSYNC     = 000010000;
+    int O_FASYNC    = 000020000;
+    int O_DIRECT    = 000040000;
+    int O_LARGEFILE = 000100000;
+    int O_DIRECTORY = 000200000;
+    int O_NOFOLLOW  = 000400000;
+    int O_NOATIME   = 001000000;
+    int O_CLOEXEC   = 002000000;
+    int __O_SYNC    = 004000000;
+    int O_PATH      = 010000000;
+    int __O_TMPFILE = 020000000;
+
+    int O_SYNC = (__O_SYNC | O_DSYNC);
+    int O_TMPFILE = (__O_TMPFILE | O_DIRECTORY);
+    int O_NDELAY = O_NONBLOCK;
 
     /* Protection bits. */
     int S_IRUSR = 00400; // Read by owner.