From 3e666656dc9ac50dd3bf36d35d70c403dd860c9f Mon Sep 17 00:00:00 2001
From: P. J. McDermott <pj@pehjota.net>
Date: Wed, 16 Mar 2022 20:06:49 -0400
Subject: main: Use difftime() instead of comparing time_t

C99 § 7.23.1 defines time_t as an "arithmetic [type] capable of
representing times" with "implementation-defined" "range and precision
of times representable".  It doesn't require that time1 > time0 for
time1 later than time0.

See also:
http://computer-programming-forum.com/47-c-language/8d7dec65bd1ddafe.htm
---
(limited to 'configure.ac')

diff --git a/configure.ac b/configure.ac
index 3ff9f79..7c94fbd 100644
--- a/configure.ac
+++ b/configure.ac
@@ -38,8 +38,9 @@ test -d "${srcdir}/.git" || CFLAGS="${save_CFLAGS}"
 funcs_missing=false
 AC_CHECK_FUNCS(
 	[\
-		calloc fprintf fputs free isspace localtime mktime printf \
-		realloc setvbuf sleep strerror strlen strftime strptime time
+		calloc difftime fprintf fputs free isspace localtime mktime \
+		printf realloc setvbuf sleep strerror strlen strftime strptime \
+		time
 	],
 	[],
 	[funcs_missing=true])
--
cgit v0.9.1