diff --git a/util/LLgen/src/main.c b/util/LLgen/src/main.c
index 509df57db..964b08c8b 100644
--- a/util/LLgen/src/main.c
+++ b/util/LLgen/src/main.c
@@ -266,6 +266,7 @@ copyfile(n) {
 		fatal(0,"Cannot open libraryfile, call an expert");
 	}
 	while ((c = getc(f)) != EOF) putc(c,fpars);
+	fclose(f);
 }
 
 install(target, source) string target, source; {