[rspivak]

Thank you for the implementations! Do you have any suggestions how to test the postscript code on mac/linux? I tried on macos using ghostscript, but I get the following error:

$ gs cat.ps helloworld.txt

Error: /undefined in ARGUMENTS ...

Thanks!

[zzo38computer]

To give command-line arguments to a PostScript program in Ghostscript, you must prefix the name of the PostScript file with two minus signs, such as:

  gs -dNODISPLAY -q -- cat.ps helloworld.txt

(The -dNODISPLAY and -q are not needed to get this PostScript program to work, but -dNODISPLAY disables graphical output, and -q avoids Ghostscript's messages getting mixed in with the PostScript program's output. You might also need -dNOSAFER; if you get a invalidaccess error, try that. As far as I know, ARGUMENTS and -- are a feature specific to Ghostscript.)