To specify the file, which is to be printed, and how the file should be handled, various commands are passed in an ESL string to the ESLPR local application using the "send" statement. The series of commands must be terminated by a line-feed (ie. \n), otherwise ESLPR will merely buffer the information until a line-feed is received.
Certain commands are dependant on the mode in which the file is being printed:
The only essential command is "FILE", although there are other basic commands that are valid regardless of the current mode specified to ESLPR.
Any command that is specified, that is not valid for the selected mode, is simply ignored.
All commands have a keyword, which must precede any parameters associated with the command and be separated by a space. The keywords are not case sensitive and must be a separate words, that is, not embedded in other words.
Parameters can contain embedded spaces, however, if the parameter contains any keyword, or a series of consecutive spaces, then it must be enclosed in double-quotes.
Note. To include a double-quote within an ESL string, use the escape sequence \".