-dnl If you use this macro in a package, you should
-dnl add the following two lines to acconfig.h:
-dnl /* Define to rpl_putenv if the replacement function should be used. */
-dnl #undef putenv
+dnl
+dnl Check whether putenv ("FOO") removes FOO from the environment.
+dnl The putenv in libc on at least SunOS 4.1.4 does *not* do that.