Hi, I am making a survey intended to be open source, which means it needs to compile everywhere, with minimal edits. I use PDFtk for post-processing the PDF output, to include something else in the PDF. This generates some temp files, that I don't want to leave in the output folder, in case someone uses them by mistake, so I want to delete them. Windows and Linux/Mac use different syntax, but "system" is a blunt tool, and does not seem to allow me to check which command to use: system "del tempfile.pdf" system "rm -f tempfile.pdf" That generates an error message, and Therion thinks the file has failed to compile when it is actually unimportant. Is it possible to code branch, like this: if( windows ) { system "del tempfile.pdf" } else { system "rm -f tempfile.pdf" } Is it possible to tell Therion not to consider the result of a "system" command when determining if compilation failed? Like using @system to ignore the output. Alternatively, does someone have a syntax of command that works on any of these three platforms? This almost works, but Linux chucks junk into a file called "nul" (even though it is not using that command): del tempfile.pdf 2>nul || rm -f tempfile.pdf 2>/dev/null And yes, I know I could demand installation of Python and clean up that way, but it seems like such overkill when all I want to do is delete a temp file. I would rather not add yet another dependency. Cheers, Tarquin