dnl This macro sets HAVE_POSIX_GETGROUPS if the
dnl getgroups() function accepts a zero first argument.
AC_DEFUN([RC_FUNC_GETGROUPS], [
	AC_CACHE_CHECK(for POSIX getgroups, rc_cv_func_posix_getgroups, AC_TRY_RUN([
#include <sys/types.h>
#include <unistd.h>
int main(void) {
	return getgroups(0, (void *)0) == -1;
}
	], rc_cv_func_posix_getgroups=yes, rc_cv_func_posix_getgroups=no, rc_cv_func_posix_getgroups=yes))
	case "$rc_cv_func_posix_getgroups" in
	yes) AC_DEFINE(HAVE_POSIX_GETGROUPS, 1, [Define to 1 if you have the `getgroups' function with POSIX semantics.]) ;;
	esac
])


dnl We can't use AC_CHECK_FUNCS for sigsetjmp(), since it's a macro in
dnl some places.
AC_DEFUN([RC_FUNC_SIGSETJMP], [
	AC_CACHE_CHECK(for sigsetjmp, rc_cv_sigsetjmp,
		AC_TRY_LINK([
#include <setjmp.h>
		], [
sigjmp_buf e;
sigsetjmp(e, 1);
		], rc_cv_sigsetjmp=yes, rc_cv_sigsetjmp=no))
	case "$rc_cv_sigsetjmp" in
	yes)	AC_DEFINE(HAVE_SIGSETJMP, 1, [Define to 1 if you have the `sigsetjmp' function or macro.]) ;;
	esac
])

dnl Similarly, AC_CHECK_FUNCS doesn't find strerror() on NetBSD.
AC_DEFUN([RC_FUNC_STRERROR], [
	AC_CACHE_CHECK(for strerror, rc_cv_strerror,
		AC_TRY_LINK([
#include <string.h>
		], [
strerror(0);
		], rc_cv_strerror=yes, rc_cv_strerror=no))
	case "$rc_cv_strerror" in
	yes)	AC_DEFINE(HAVE_STRERROR, 1, [Define to 1 if you have the `strerror' function or macro.]) ;;
	esac
])

dnl HPUX needs _KERNEL defined to pick up RLIMIT_foo defines.  (Why?)
AC_DEFUN([RC_NEED_KERNEL], [
	AC_CACHE_CHECK(if _KERNEL is required for RLIMIT defines, rc_cv_kernel_rlimit,
		AC_TRY_COMPILE([
#include <sys/types.h>
#include <sys/resource.h>
		], [
int f;
f = RLIMIT_DATA;
		], rc_cv_kernel_rlimit=no, [ AC_TRY_COMPILE([
#include <sys/types.h>
#define _KERNEL
#include <sys/resource.h>
#undef _KERNEL
			], [
int f;
f = RLIMIT_DATA;
			], rc_cv_kernel_rlimit=yes, rc_cv_kernel_rlimit=no)]))
	case "$rc_cv_kernel_rlimit" in
	yes)	AC_DEFINE(RLIMIT_NEEDS_KERNEL, 1, [Define to 1 if `_KERNEL' must be defined for `RLIMIT_*' macros.]) ;;
	esac
])

dnl Look for rlim_t in sys/types.h and sys/resource.h
AC_DEFUN([RC_TYPE_RLIM_T], [
	AC_CACHE_CHECK(for rlim_t, rc_cv_have_rlim_t,
		AC_EGREP_CPP(rlim_t, [
#include <sys/types.h>
#if RLIMIT_NEEDS_KERNEL
#define _KERNEL
#endif
#include <sys/resource.h>
		], rc_cv_have_rlim_t=yes, rc_cv_have_rlim_t=no))

	case "$rc_cv_have_rlim_t" in
	yes)	AC_DEFINE(HAVE_RLIM_T, 1, [Define to 1 if you have the `rlim_t' type.]) ;;
	no)	AC_CACHE_CHECK(for native quad_t, rc_cv_have_quad_t,
			AC_TRY_COMPILE([
#include <sys/types.h>
			], [
typedef quad_t align_t;
align_t a;
a = (quad_t)0;
			], rc_cv_have_quad_t=yes, rc_cv_have_quad_t=no))

		case "$rc_cv_have_quad_t" in
		yes)	AC_DEFINE(HAVE_QUAD_T, 1, [Define to 1 if you have the `quad_t' type.])
			AC_CACHE_CHECK(if rlimit values are quad_t, rc_cv_rlim_t_is_quad_t,
				AC_TRY_RUN([
#include <sys/types.h>
#include <sys/time.h>
#include <sys/types.h>
#if RLIMIT_NEEDS_KERNEL
#define _KERNEL
#endif
#include <sys/resource.h>
#if RLIMIT_NEEDS_KERNEL
#undef _KERNEL
#endif
main(){
	struct rlimit rl;
	exit(sizeof rl.rlim_cur != sizeof(quad_t));
}
				], rc_cv_rlim_t_is_quad_t=yes, rc_cv_rlim_t_is_quad_t=no, $ac_cv_type_quad_t))

			case "$rc_cv_rlim_t_is_quad_t" in
			yes)	AC_DEFINE(RLIM_T_IS_QUAD_T, 1, [Define to 1 if `rlim_t' is `quad_t'.]) ;;
			esac
			;;
		esac
		;;
	esac
])


dnl Check type of sig_atomic_t.
AC_DEFUN([RC_TYPE_SIG_ATOMIC_T], [
	AC_CACHE_CHECK(for sig_atomic_t, rc_cv_sig_atomic_t,
		AC_EGREP_HEADER(sig_atomic_t, signal.h,
			rc_cv_sig_atomic_t=yes, rc_cv_sig_atomic_t=no))
	case "$rc_cv_sig_atomic_t" in
	no)	AC_DEFINE(sig_atomic_t, int, [Define to 1 if you have the `sig_atomic_t' type.]) ;;
	esac
])


dnl Do we have /dev/fd or /proc/self/fd?
AC_DEFUN([RC_SYS_DEV_FD], [
	AC_CACHE_CHECK(for /dev/fd, rc_cv_sys_dev_fd,
		if test -d /dev/fd && test -r /dev/fd/0; then
			rc_cv_sys_dev_fd=yes
		elif test -d /proc/self/fd && test -r /proc/self/fd/0; then
			rc_cv_sys_dev_fd=odd
		else
			rc_cv_sys_dev_fd=no
		fi
	)
])


dnl Can mknod make FIFOs?
AC_DEFUN([RC_SYS_MKNOD_FIFO], [
	AC_CACHE_CHECK(for mknod FIFOs, rc_cv_sys_fifo,
		AC_TRY_RUN([
#include <sys/types.h>
#include <sys/stat.h>

main() {
	exit(mknod("/tmp/rc$$.0", S_IFIFO | 0666, 0) != 0);
}
		], rc_cv_sys_fifo=yes, rc_cv_sys_fifo=no, rc_cv_sys_fifo=no))
	rm -f /tmp/rc$$.0
	case "$rc_cv_sys_fifo" in
	yes)	AC_DEFINE(HAVE_FIFO) ;;
	esac
])

dnl Where is tgetent()?
AC_DEFUN([RC_LIB_TGETENT], [
	AC_CHECK_LIB(tinfo, tgetent,
		rc_lib_tgetent=-ltinfo,
		AC_CHECK_LIB(termcap, tgetent,
			rc_lib_tgetent=-ltermcap,
			AC_CHECK_LIB(ncurses, tgetent,
				rc_lib_tgetent=-lncurses,
				AC_MSG_ERROR(tgetent not found)
			)
		)
	)
])