diff --git a/libsrc/common/fgets.c b/libsrc/common/fgets.c
index ab755616a..e65fb4bc8 100644
--- a/libsrc/common/fgets.c
+++ b/libsrc/common/fgets.c
@@ -25,8 +25,7 @@ char* __fastcall__ fgets (char* s, unsigned size, FILE* f)
 
     if (size == 0) {
         /* Invalid size */
-        _errno = EINVAL;
-        return 0;
+        return (char*) _seterrno (EINVAL);
     }
 
     /* Read input */