diff --git a/ykpamcfg.c b/ykpamcfg.c
index d2ad7b5..fece317 100644
--- a/ykpamcfg.c
+++ b/ykpamcfg.c
@@ -39,6 +39,7 @@
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <fcntl.h>
+#include <limits.h>
 
 #include <ykpers.h>
 
@@ -164,8 +165,8 @@ do_add_hmac_chalresp(YK_KEY *yk, uint8_t slot, bool verbose, char *output_dir, u
   */
   
   if (!output_dir){
-      char fullpath[256];
-      snprintf(fullpath, 256,"%s/.yubico",p->pw_dir);
+      char fullpath[PATH_MAX];
+      snprintf(fullpath, PATH_MAX, "%s/.yubico", p->pw_dir);
       
       //check if directory exists     
       if (stat(fullpath,&st)!=0 ){