diff --git a/src/misc/getopt_long.c b/src/misc/getopt_long.c
index 008b747..ddcef94 100644
--- a/src/misc/getopt_long.c
+++ b/src/misc/getopt_long.c
@@ -1,5 +1,7 @@
 #define _GNU_SOURCE
 #include <stddef.h>
+#include <stdlib.h>
+#include <limits.h>
 #include <getopt.h>
 #include <stdio.h>
 #include <string.h>
@@ -58,10 +60,10 @@ static int __getopt_long_core(int argc, char *const *argv, const char *optstring
 	{
 		int colon = optstring[optstring[0]=='+'||optstring[0]=='-']==':';
 		int i, cnt, match;
-		char *arg, *opt;
+		char *arg, *opt, *start = argv[optind]+1;
 		for (cnt=i=0; longopts[i].name; i++) {
 			const char *name = longopts[i].name;
-			opt = argv[optind]+1;
+			opt = start;
 			if (*opt == '-') opt++;
 			while (*opt && *opt != '=' && *opt == *name)
 				name++, opt++;
@@ -74,6 +76,17 @@ static int __getopt_long_core(int argc, char *const *argv, const char *optstring
 			}
 			cnt++;
 		}
+		if (cnt==1 && longonly && arg-start == mblen(start, MB_LEN_MAX)) {
+			int l = arg-start;
+			for (i=0; optstring[i]; i++) {
+				int j;
+				for (j=0; j<l && start[j]==optstring[i+j]; j++);
+				if (j==l) {
+					cnt++;
+					break;
+				}
+			}
+		}
 		if (cnt==1) {
 			i = match;
 			opt = arg;