1 files changed, 2 insertions, 2 deletions
diff --git a/adig.c b/adig.c
index 80ee7f4..fb3a432 100644
--- a/adig.c
+++ b/adig.c
@@ -225,7 +225,7 @@ int main(int argc, char **argv)
 
         case 'T':
           /* Set the TCP port number. */
-          if (!isdigit((unsigned char)*optarg))
+          if (!ISDIGIT(*optarg))
             usage();
           options.tcp_port = (unsigned short)strtol(optarg, NULL, 0);
           optmask |= ARES_OPT_TCP_PORT;
@@ -233,7 +233,7 @@ int main(int argc, char **argv)
 
         case 'U':
           /* Set the UDP port number. */
-          if (!isdigit((unsigned char)*optarg))
+          if (!ISDIGIT(*optarg))
             usage();
           options.udp_port = (unsigned short)strtol(optarg, NULL, 0);
           optmask |= ARES_OPT_UDP_PORT;