Return ERROR_DISK_FULL for WriteFile.

diff --git a/files/file.c b/files/file.c
index edce507..5734cbb 100644
--- a/files/file.c
+++ b/files/file.c
@@ -1144,6 +1144,9 @@
     {
         if ((errno == EAGAIN) || (errno == EINTR)) continue;
         if ((errno == EFAULT) && VIRTUAL_HandleFault( buffer )) continue;
+        if (errno == ENOSPC)
+            SetLastError( ERROR_DISK_FULL );
+        else
         FILE_SetDosError();
         break;
     }