As this problem indeed is nontrivial, the product in question is not any kind of "adapter" or "cable", but an active software product that only can support some printers. This is explained behind the link you gave, but just as a reminder, it will only work on some printers, but it's not a drop-in solution because some printers require their own, custom drivers and you cannot install them on the PC (your RS232 host); the support must be in that converter product. So better check first if the potential printers are compatible. The "linux driver" hint is a clue, but not a definitive answer; some printers may have a linux driver available, but still use their own custom communication.