How To Block Email Using Subject Headers In Postfix

Author: , December 7th, 2021

I needed to block email based on the Subject header. The solution is simple: Edit as root and uncomment or add:

Next, creaate or edit /etc/postfix/header_checks as root and add the following line:

Finally, run sudo postfix reload NOTE: Do NOT add the “i” after the regular expression! It is case-insensitive by […]

How To Install/Update CPAN on MacOS Mojave with fatal error: ‘EXTERN.h’ file not found

Author: , June 12th, 2019

The Problem Tried to install the latest version of cpan and got stuck. Tracked it down to the dependency module Mac::SystemDirectory which was failing to build:

The Solution Use the MacOS installer command to deploy the needed files:

The, rerunning the cpan install works:

How To Allow Cross-Site Javascript Using Apache

Author: , September 24th, 2015

The key is to send a response header like this: Access-Control-Allow-Origin: * In the Apache web server, one enables this via the following directive: Header set Access-Control-Allow-Origin * This requires the use of mod_headers, which is enabled by default in Apache. For example: