#18 configure.ac: don't use the deprecated AC_OUTPUT form

[Yegor Yefremov]

Specify Makefiles via the AC_CONFIG_FILES command and use AC_OUTPUT
without parameters.

Resolve the following warning:

configure.ac:161: warning: AC_OUTPUT should be used without arguments.

[Yegor Yefremov]

This is the full autoconf log with more warnings:

configure.ac:6: warning: AM_INIT_AUTOMAKE: two- and three-arguments
forms are deprecated.
./lib/autoconf/general.m4:2434: AC_DIAGNOSE is expanded from...
aclocal.m4:429: AM_INIT_AUTOMAKE is expanded from...
configure.ac:6: the top level
configure.ac:13: warning: 'AM_CONFIG_HEADER': this macro is obsolete.
configure.ac:13: You should use the 'AC_CONFIG_HEADERS' macro instead.
aclocal.m4:743: AM_CONFIG_HEADER is expanded from...
configure.ac:13: the top level
configure.ac:33: warning: The macro 'AC_HEADER_STDC' is obsolete.
configure.ac:33: You should run autoupdate.
./lib/autoconf/headers.m4:663: AC_HEADER_STDC is expanded from...
configure.ac:33: the top level
configure.ac:42: warning: The macro 'AC_STRUCT_ST_RDEV' is obsolete.
configure.ac:42: You should run autoupdate.
./lib/autoconf/types.m4:1067: AC_STRUCT_ST_RDEV is expanded from...
configure.ac:42: the top level
configure.ac:43: warning: The macro 'AC_HEADER_TIME' is obsolete.
configure.ac:43: You should run autoupdate.
./lib/autoconf/headers.m4:702: AC_HEADER_TIME is expanded from...
configure.ac:43: the top level
configure.ac:47: warning: The macro 'AC_PROG_GCC_TRADITIONAL' is obsolete.
configure.ac:47: You should run autoupdate.
./lib/autoconf/c.m4:1676: AC_PROG_GCC_TRADITIONAL is expanded from...
configure.ac:47: the top level
configure.ac:48: warning: The macro 'AC_TYPE_SIGNAL' is obsolete.
configure.ac:48: You should run autoupdate.
./lib/autoconf/types.m4:805: AC_TYPE_SIGNAL is expanded from...
configure.ac:48: the top level
configure.ac:161: warning: AC_OUTPUT should be used without arguments.
configure.ac:161: You should run autoupdate.
configure.ac:6: warning: AM_INIT_AUTOMAKE: two- and three-arguments
forms are deprecated. For more info, see:
configure.ac:6:
https://www.gnu.org/software/automake/manual/automake.html#Modernize-AM_005fINIT_005fAUTOMAKE-invocation

I am using autoreconf (GNU Autoconf) 2.72.

I am not an autoconf expert. So could you look at this?

[Paul Crawford]

Sadly I am also very ignorant in the ways of the automated build tools. Generally it has been Michael Meskes who has dealt with the tools relating to package management, etc.

[Yegor Yefremov]

I think, this patch is safe (at least I could successfully configure and build watchdog). But other warnings require more careful checks.

Our new projects use CMake, I have also converted some older projects to CMake. But I also have some experince with meson.