diff --git a/unixtime.c b/unixtime.c
index 0a3cc46..b813a64 100644
--- a/unixtime.c
+++ b/unixtime.c
@@ -82,16 +82,16 @@ int main(int argc, char** argv) {
 			t = atol(argv[i]);
 			l = strlen(argv[i]);
 			if((p = malloc(l + 1)) != NULL) {
-				snprintf(p, l + 1, "%d", t);
+				snprintf(p, l + 1, "%ld", t);
 				if(strcmp(argv[i], p)) {
-					fprintf(stderr, "%s: not numeric: %s\n", progname, 
+					fprintf(stderr, "%s: not integer: %s\n", progname, 
 						argv[i]);
 					exit(EX_DATAERR);
 				}
 				free(p);
 			} else {
 				fprintf(stderr, "%s: Warning: cannot allocate memory"
-					" to do numeric test on input.\n", progname);
+					" to do integer test on input.\n", progname);
 			}
 			break;
 		}
@@ -99,7 +99,7 @@ int main(int argc, char** argv) {
 
 	p = ctime((& t));
 	if(p == NULL) {
-		fprintf(stderr, "%s: unrecognized date '%d'.\n", progname, time);
+		fprintf(stderr, "%s: unrecognized date '%ld'.\n", progname, t);
 		exit(EX_DATAERR);
 	}
 	fputs(p, stdout);