a576ddfd_PHP__Runkit_Sandbox___Manual_x_Settings___Status_Indicators_Purpose
[Setting] output_handler [Type] Callback [Default] None [Purpose] 
When set to a valid callback, all output generated by the Sandbox instance will be processed through the named function. Sandbox output handlers follow the same calling conventions as the system-wide output handler.
PHP: Runkit_Sandbox - Manual
Purpose