dnl Many of the following macros courtesy of:dnl http://www.gnu.org/software/ac-archive/dnldnl The Following macros courtesy of:dnl Installed_Packages/check_gnu_make.htmldnl dnl Copyrights are by the individual authors, as listed.dnl License: GPLdnldnl CHECK_GNU_MAKE()dnldnl This macro searches for a GNU version of make.  If a match is found, thednl makefile variable `ifGNUmake' is set to the empty string, otherwise it isdnl set to "#".  This is useful for  including a special features in a Makefile,dnl which cannot be handled by other versions of make.  The variablednl _cv_gnu_make_command is set to the command to invoke GNU make if it exists,dnl the empty string otherwise.dnldnl Here is an example of its use:dnldnl Makefile.in might contain:dnldnl     # A failsafe way of putting a dependency rule into a makefilednl     $(DEPEND):dnl             $(CC) -MM $(srcdir)/*.c > $(DEPEND)dnldnl     @ifGNUmake@ ifeq ($(DEPEND),$(wildcard $(DEPEND)))dnl     @ifGNUmake@ include $(DEPEND)dnl     @ifGNUmake@ endifdnldnl Then configure.in would normally contain:dnldnl     CHECK_GNU_MAKE()dnl     AC_OUTPUT(Makefile)dnldnl Then perhaps to cause gnu make to override any other make, we could dodnl something like this (note that GNU make always looks for GNUmakefile first):dnldnl     if  ! test x$_cv_gnu_make_command = x ; thendnl             mv Makefile GNUmakefilednl             echo .DEFAULT: > Makefile ;dnl             echo \  $_cv_gnu_make_command \$@ >> Makefile;dnl     fidnldnl Then, if any (well almost any) other make is called, and GNU make also exists,dnl then the other make wraps the GNU make.dnldnl John Darrington <j.darrington@elvis.murdoch.edu.au>dnl 1.3 (2002/01/04)dnldnl Modified 18 Sep 2002 by Jon Nelson <jnelson@boa.org>AC_DEFUN([CHECK_GNU_MAKE],          [ AC_CACHE_CHECK( for GNU make, _cv_gnu_make_command,           [_cv_gnu_make_command=''           dnl Search all the common names for GNU make           for a in "$MAKE" make gmake gnumake ; do             if test -z "$a" ; then continue ; fi             if ( sh -c "$a --version" 2> /dev/null | grep GNU  2>&1 > /dev/null ); then               _cv_gnu_make_command=$a               break;             fi           done           if test "x$_cv_gnu_make_command" = "x"; then             _cv_gnu_make_command="Not found"           fi           ])dnl If there was a GNU version, then set @ifGNUmake@ to the empty string, '#' otherwise         if test "$_cv_gnu_make_command" != "Not found"; then           ifGNUmake='';         else           ifGNUmake='#';           _cv_gnu_make_command='';         fi         AC_SUBST(ifGNUmake)        ])dnl AC_CHECK_STRUCT_FOR(INCLUDES,STRUCT,MEMBER,DEFINE,[no]) dnl 1.1 (2000/09/19) dnl Wes Hardaker <wjhardaker@ucdavis.edu> dnl ----------------------------------------------------------AC_DEFUN([AC_CHECK_STRUCT_FOR],[ac_safe_struct=`echo "$2" | sed 'y%./+-%__p_%'`ac_safe_member=`echo "$3" | sed 'y%./+-%__p_%'`ac_safe_all="ac_cv_struct_${ac_safe_struct}_has_${ac_safe_member}"changequote(, )dnl  ac_uc_define=STRUCT_`echo "${ac_safe_struct}_HAS_${ac_safe_member}" | sed 'y%abcdefghijklmnopqrstuvwxyz./-%ABCDEFGHIJKLMNOPQRSTUVWXYZ___%'`changequote([, ])dnlAC_MSG_CHECKING([for $2.$3])AC_CACHE_VAL($ac_safe_all,[if test "x$4" = "x"; then  defineit="= 0"elif test "x$4" = "xno"; then  defineit=""else  defineit="$4"fiAC_TRY_COMPILE([$1],[struct $2 testit;testit.$3 $defineit;], eval "${ac_safe_all}=yes", eval "${ac_safe_all}=no" )])if eval "test \"x$`echo ${ac_safe_all}`\" = \"xyes\""; then  AC_MSG_RESULT(yes)  AC_DEFINE_UNQUOTED($ac_uc_define)else  AC_MSG_RESULT(no)fi])dnl @synopsis AC_C_VAR_FUNCdnldnl This macro tests if the C complier supports the C9X standarddnl __func__ indentifier.dnldnl The new C9X standard for the C language stipulates that thednl identifier __func__ shall be implictly declared by the compilerdnl as if, immediately following the opening brace of each functiondnl definition, the declarationdnldnl     static const char __func__[] = "function-name";dnldnl appeared, where function-name is the name of the function wherednl the __func__ identifier is used.dnldnl @author Christopher Currie <christopher@currie.com>AC_DEFUN([AC_C_VAR_FUNC],[AC_REQUIRE([AC_PROG_CC])AC_CACHE_CHECK(whether $CC recognizes __func__, ac_cv_c_var_func,AC_TRY_COMPILE(,[int main() {char *s = __func__;}],AC_DEFINE(HAVE_FUNC,,[Define if the C complier supports __func__]) ac_cv_c_var_func=yes,ac_cv_c_var_func=no) )])dnldnl Exports one of ac_cv_func_poll or ac_cv_func_selectdnl Author - Jon Nelson <jnelson@boa.org> dnl Copyright 2002AC_DEFUN([POLL_OR_SELECT],  [    AC_MSG_CHECKING(whether to use poll or select)    AC_ARG_WITH(poll,    [  --with-poll             Use poll],    [      if test "$withval" = "yes" ; then        AC_MSG_RESULT(trying poll)        ac_x=1      else        AC_MSG_RESULT(trying select)        ac_x=0      fi    ],    [      AC_MSG_RESULT(trying select)      ac_x=0    ])    if test $ac_x = 1; then      AC_CHECK_HEADERS(sys/poll.h)      AC_CHECK_FUNCS(poll)      if test "x$ac_cv_func_poll" = "x"; then        AC_MSG_ERROR(We attempted to find poll but could not. Please try again with --without-poll)      fi      BOA_ASYNC_IO="poll"    else      AC_CHECK_HEADERS(sys/select.h)      AC_CHECK_FUNCS(select)      if test "x$ac_cv_func_select" = "x"; then        AC_MSG_ERROR(We attempted to find select but could not. Please try again with --with-poll)      fi      BOA_ASYNC_IO="select"    fi  ])