lprint and ZPL files - how does lprint decide whether to "rasterize" a file - or just send it unaltered to printer

[brianbarr]

What logic does lprint use to decide whether to send input data to a printer specific rasterizer and then on to the printer - or pass the data unaltered (such as a raw print queue does in cups) If I send a zebra printer a zpl file, how does lprint decide to just pass the zpl file unaltered to the printer vs input data such as a jpg or pdf? File naming such as label.zpl?

[michaelrsweet]

LPrint looks at the document format sent by the print command/client or, if the default "auto" (application/octet-stream) format is specified then it looks at the contents of the file. At present the ZPL check looks for the file to start with "^" followed by an uppercase letter.