Up: Gateways in general

5.3.1 Suppressing Network Connections

In some circumstances it is desirable to suppress making network connections. A typical case is when rendering HTML in a mail user agent, when external URLs should not be activated, particularly to avoid “bugs” which “call home” by fetch single-pixel images and the like. To arrange this, bind the following variable for the duration of such processing.

— Variable: url-gateway-unplugged

If this variable is non-nil new network connections are never opened by the URL library.