(jm_PREREQ_HUMAN): New macro.

(jm_PREREQ): Use it.

m4/prereq.m4

@@ -1,4 +1,4 @@
-#serial 6
+#serial 7
 
 dnl These are the prerequisite macros for files in the lib/
 dnl directories of the fileutils, sh-utils, and textutils packages.
@@ -9,6 +9,7 @@ AC_DEFUN(jm_PREREQ,
   jm_PREREQ_CANON_HOST
   jm_PREREQ_ERROR
   jm_PREREQ_GETPAGESIZE
+  jm_PREREQ_HUMAN
   jm_PREREQ_QUOTEARG
   jm_PREREQ_READUTMP
   jm_PREREQ_REGEX
@@ -37,6 +38,16 @@ AC_DEFUN(jm_PREREQ_CANON_HOST,
                    netinet/in.h arpa/inet.h)
 ])
 
+# If you use human.c, you need the following files:
+# uintmax_t.m4 inttypes_h.m4 ulonglong.m4
+AC_DEFUN(jm_PREREQ_HUMAN,
+[
+  AC_CHECK_HEADERS(limits.h stdlib.h string.h)
+  AC_CHECK_DECLS((getenv))
+  AC_REQUIRE([jm_AC_HEADER_INTTYPES_H])
+  AC_REQUIRE([jm_AC_TYPE_UINTMAX_T])
+])
+
 AC_DEFUN(jm_PREREQ_GETPAGESIZE,
 [
   AC_CHECK_FUNCS(getpagesize)