AC_CHECK_FUNCS([strcasecmp strncasecmp ctermid times gmtime_r strtoull])
AC_CHECK_FUNCS([setenv unsetenv fcntl ftruncate inet_ntop])
AC_CHECK_FUNCS([canonicalize_file_name])
+AC_CHECK_FUNCS([prctl])
AC_CHECK_FUNCS([gettimeofday getrusage getrlimit setrlimit clock_gettime])
AC_CHECK_FUNCS([atexit raise getpagesize strftime nl_langinfo setlocale])
AC_CHECK_FUNCS([waitpid wait4 sigaction sigprocmask pipe getaddrinfo])