diff --git a/src/proto/strings.pro b/src/proto/strings.pro
index b792edc..c25555f 100644
--- a/src/proto/strings.pro
+++ b/src/proto/strings.pro
@@ -17,6 +17,7 @@
 int vim_strnicmp(char *s1, char *s2, size_t len);
 int vim_strnicmp_asc(char *s1, char *s2, size_t len);
 char_u *vim_strchr(char_u *string, int c);
+char *vim_strnchr(const char *p, size_t *n, int c);
 char_u *vim_strbyte(char_u *string, int c);
 char_u *vim_strrchr(char_u *string, int c);
 void sort_strings(char_u **files, int count);