AC_DIR_HEADERS is hasbeen'ed.
* acspecific.m4 (AC_DIR_HEADER): Raised from obsolete to hasbeen.
* acspecific.m4 (AC_CHECK_HEADERS_DIRENT, AC_CHECK_HEADER_DIRENT):
Removed, were used only by AC_DIR_HEADER and were not documented.
* autoheader.m4: Remove the hooks for AC_CHECK_HEADERS_DIRENT.
* autoconf.texi (Particular Headers): Removed the documentation of
AC_DIR_HEADER.
* autoconf.texi (Environment Variables): Remove the very last
traces of documentation of --env-VAR.
* install.texi: Give emore details on envvar handling.
* acgeneral.m4 (AC_HELP_STRING): Add a third argument to tune the
width of the first column.
(AC_INIT_NOTICE): Initialize ac_arg_enable_help, ac_arg_with_help,
and ac_arg_var_help.
* acgeneral.m4 (AC_INIT_PARSE_ARGS): Remove the handling of
--env-var=. After debate, the solution chosen to specify envvars
to configure is a` la make: ./configure VAR=VAL.
(AC_INIT_PARSE_ARGS, --help): Output ac_arg_enable_help,
ac_arg_with_help, and ac_arg_var_help.
* acgeneral.m4 (AC_ARG_VAR): New macro, to register and document
influent envvars.
* acspecific.m4 (AC_PROG_CC): Document CFLAGS.
This is mainly to test AC_ARG_VAR. Var to document are to be
defined.
