diff --git a/libc/stdio/vscanf_callback.cpp b/libc/stdio/vscanf_callback.cpp
index 3adbd48e..32efcc14 100644
--- a/libc/stdio/vscanf_callback.cpp
+++ b/libc/stdio/vscanf_callback.cpp
@@ -108,7 +108,10 @@ int vscanf_callback(void* fp,
 		{
 		case MODE_INIT:
 			if ( !*format )
+			{
+				ungetc(ic, fp);
 				goto break_loop;
+			}
 			if ( isspace(*formatuc) )
 			{
 				if ( isspace(ic) )