Fix error behavior.

src/core/org/luaj/vm2/lib/IoLib.java

@@ -270,7 +270,7 @@ public class IoLib extends OneArgFunction {
 				f = checkfile(env);
 				return freadline(f);
 			}
-		} catch ( Exception ioe ) {
+		} catch ( IOException ioe ) {
 			return errorresult(ioe);
 		}
 		return NONE;
@@ -319,10 +319,14 @@ public class IoLib extends OneArgFunction {
 		return varargsOf(NIL, valueOf(errortext));
 	}
 
-	private Varargs lines(final File f) throws Exception {
+	private Varargs lines(final File f) {
+		try {
 			IoLib iter = (IoLib) getClass().newInstance();
 			iter.setfenv(f);
 			return iter.bindv("lnext",LINES_ITER);
+		} catch ( Exception e ) {
+			return error("lines: "+e);
+		}
 	}
 
 	private static Varargs iowrite(File f, Varargs args) throws IOException {

test/lua/iolib.lua

@@ -111,7 +111,11 @@ print( "a:read", ( a:read(7) ) )
 print( "b:read", ( b:read(7) ) ) 
 --]]
 
-local pcall = function(...)	return ( pcall(...) )end
+local pcall = function(...)	
+	local s,e  = pcall(...)
+	if s then return s end
+	return s,e:match("closed")
+end
 
 print( 'a:close', pcall( a.close, a ) )
 print( 'a:write', pcall( a.write, a, 'eee') )