You want to print two copies of a voucher in ESC / POS language, but I can not find the function in the documentation to do it
just as there is a command to cut the paper
$ printer-> cut ();
just as there is a command to feed the paper
$ printer-> feed (3);
There is not one that, when I pass a certain parameter, prints a voucher n times?
This is not possible with ESC/POS. You have to send all data three times if you want three copies.