I just spent the last few days trying to figure out something odd. When I pasted certain lines to post in WordPress, it would cause a 503 error. I eventually narrowed it down to a few particular lines in my last example:
$mydebug = fopen('debug.txt','a'); in a post it causes a 503 error $file_contents = curl_exec($ch); fwrite($mydebug,"/nHttp Code: $httpCode/n");
Each one would throw a Service Unavailable 503 error. I got around the problem by tossing a space between the parenthesis and semi-colon but it still bothered me.
Turns out it wasn’t WordPress at all, but rather the Apache module mod_security. This post tells the whole story. The quick fix is to create/modify your wp-admin .htaccess file to include:
SecFilterEngine Off
After that I could easily post this message without flubbing my code.