[NTG-context] how to set the name of outputfile using a value defined in the source

Hi all, I'm getting back to using ConTeXt after a couple of years, so I might be missing something obvious... I would like to add an I.D. code to the name of my outputfile, but since this will be used in an automated environment I would like to load the ID-code from the source file. MWE: test.tex \starttext \def\idcode{something} Some text, whatever. \stoptext If I typeset with: context text --result=test-idcode the result is obviously "test-idcode.pdf", but I want to get a file name: "test-something.pdf" Is this possible? Thanks, Jelle