diff --git a/cmdline/mingw.c b/cmdline/mingw.c
index b45411bd..41f61172 100644
--- a/cmdline/mingw.c
+++ b/cmdline/mingw.c
@@ -567,7 +567,10 @@ static void windows_errno(DWORD error)
 {
 	switch (error) {
 	case ERROR_INVALID_HANDLE :
-		errno = EBADF;
+		/* we check for a bad handle calling _get_osfhandle() */
+		/* and in such case we return EBADF */
+		/* Other cases are here identified with EINVAL */
+		errno = EINVAL;
 		break;
 	case ERROR_FILE_NOT_FOUND :
 	case ERROR_PATH_NOT_FOUND : /* in GetFileAttributeW() if internal path not found */
@@ -791,6 +794,29 @@ int windows_ftruncate(int fd, off64_t off)
 	return 0;
 }
 
+int windows_fsync(int fd)
+{
+	HANDLE h;
+
+	if (fd == -1) {
+		errno = EBADF;
+		return -1;
+	}
+
+	h = (HANDLE)_get_osfhandle(fd);
+	if (h == INVALID_HANDLE_VALUE) {
+		errno = EBADF;
+		return -1;
+	}
+
+	if (!FlushFileBuffers(h)) {
+		windows_errno(GetLastError());
+		return -1;
+	}
+
+	return 0;
+}
+
 int windows_futimens(int fd, struct windows_timespec tv[2])
 {
 	HANDLE h;
diff --git a/cmdline/mingw.h b/cmdline/mingw.h
index 351e4327..0b2a5dc2 100644
--- a/cmdline/mingw.h
+++ b/cmdline/mingw.h
@@ -54,7 +54,7 @@
 #define ftruncate windows_ftruncate
 #define HAVE_FSYNC 1
 #undef fsync
-#define fsync _commit
+#define fsync windows_fsync
 #undef rename
 #define rename windows_rename
 #undef remove
@@ -191,6 +191,11 @@ int lstat_ex(const char* file, struct windows_stat* st);
  */
 int windows_ftruncate(int fd, off64_t off);
 
+/**
+ * Like the C fsync().
+ */
+int windows_fsync(int fd);
+
 /**
  * Like the C futimes().
  */