+AC_CHECK_FUNCS(getlogin cuserid getpwnam getpwuid getpwent getgrnam getgrgid getgrent)
+AC_CHECK_FUNCS(getlogin_r getpwnam_r getpwuid_r getgrnam_r getgrgid_r)
+AC_CHECK_FUNCS(getservent getservbyname getservbyport getaddrinfo gai_strerror)
+AC_CHECK_FUNCS(getprotoent getprotobyname getprotobynumber)
+AC_CHECK_FUNCS(getmntent setmntent addmntent)
+AC_CHECK_FUNCS(inet_ntoa mmap munmap)