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diff --git a/src/os/win32/ngx_files.h b/src/os/win32/ngx_files.h
index 5aef0b6ef5ab3715af81f98719d4416dc7d76ee4..132b6221b52f3374365a8173a94c43fe31a880a3 100644 (file)
--- a/src/os/win32/ngx_files.h
+++ b/src/os/win32/ngx_files.h
@@ -27,6 +27,9 @@
 #define NGX_FILE_ERROR              0
 
 
+/*
+ * FILE_FLAG_BACKUP_SEMANTICS allows to obtain a handle to a directory
+ */
 
 #define ngx_open_file(name, mode, create, access)                            \
     CreateFile((const char *) name, mode,                                    \