4. The method as recited in claim 1 wherein said peripheral unit is initially interpreting said second control language instead of said first control language, said method comprising the added steps of: determining whether a next command is an end of job marker; If yes, identifying a control language from the input data; If no, determining whether a next character is an escape character; if no, processing a next command; if yes, determining whether said peripheral unit is in a binary input/output mode; if yes, processing a next command; if no, determining if a language boundary has occurred.
1. In a peripheral unit for creating marked pages, said peripheral unit adapted to receive, interpret and respond to a plurality of control languages that may appear in an input data stream, a method for identifying occurrence of a language boundary between a first control language and a second control language, said language boundary indicating a cessation of commands configured in accord with said first control language and a commencement of commands configured in accord with said second control language, comprising the steps of: (a) determining if a command in said data stream requires a printing of an initial mark on a page and, if yes; (b) instituting a subroutine to further determine if a language boundary has been encountered; and (c) if yes, identifying a control language of the input data stream.