diff --git a/toys/posix/grep.c b/toys/posix/grep.c
index c7b44e5..891f760 100644
--- a/toys/posix/grep.c
+++ b/toys/posix/grep.c
@@ -102,7 +102,10 @@
     int mmatch = 0;
 
     lcount++;
-    if (0 > (len = getdelim(&line, &unused, TT.indelim, file))) break;
+    errno = 0;
+    len = getdelim(&line, &unused, TT.indelim, file);
+    if (errno) perror_msg("%s", name);
+    if (len<1) break;
     if (line[len-1] == TT.indelim) line[len-1] = 0;
 
     start = line;