Hi, I wish to use subst function and looked into module textops documentation to know how to use it. The documentation provides an example which is using a variable or flag named \u. Looks like this '\u' is a replacement for the current uri of the SIP request. # replace the uri in to: with the message uri (just an example) if ( subst('/^To:(.*)sip:[^@]*@[a-zA-Z0-9.]+(.*)$/t:\1\u\2/ig') ) {}; So, I would like to know if there are more variables like this one that can be used with subst ? And are there variables too for log function that can be used the same way ? Thanks,