1 files changed, 3 insertions, 0 deletions
diff --git a/dupfiles.1 b/dupfiles.1
index ee66d9b..ef0eaa8 100644
--- a/dupfiles.1
+++ b/dupfiles.1
@@ -36,6 +36,9 @@ Note that after hardlinking, the files are the same file:
 if you modify one, both names show the modified file.
 Thus, if you the files should not be the same file, but just copies of
 each other, do not hardlink them together.
+.PP
+Files must have same owner, same group, and same permissions bits
+to be hardlinked together.
 .SH OPTIONS
 .TP
 .BR --progress