diff --git a/nselib/datafiles.lua b/nselib/datafiles.lua
index 159119280..32611f557 100644
--- a/nselib/datafiles.lua
+++ b/nselib/datafiles.lua
@@ -137,6 +137,7 @@ end
 -- taken by <code>parse_lines</code>.
 -- @param filename Name of the file to parse.
 -- @param ... A table of capture patterns.
+-- @return Boolean status, false on failure
 -- @return A table whose structure mirrors that of the capture table,
 -- filled in with captured values.
 function parse_file(filename, ...)