I have printed text based labels using Zebra printers but not bar codes. I know of no way for FM to send any type of command to a printer least of all in a properitery language. My guess is you will have to load a bar code font.
But there might be some URL-command or other command to call the printer-driver and make it print my scripted text (as then would be interpretated by the printer as barcode).
If anyone has clues to this please assist.
I am searching for a similar solution. I am converting an Access application that uses VB to print barcodes on a Zebra GK420t desktop printer. The VB app sends ZPL strings to print the labels. I know that it has been some time since your post but if you found a solution I would much appreciate some guidance. The converted application will run on FM 13 server with users running Mac and Windows. Labels will be printed mostly from the Windows machines. However, there may be occasional Mac users printing barcode labels.
With guidance from others I have gotten this to work within FileMaker. As you stated, you need to format a text file with ZPL commands embedded with data. In my case it was a food processing operation that needed to print labels to attach to packages on the last step of the process. I created a file (PrintCommands) within FM that contained the proper ZPL commands with placeholders for the data, one record for each ZPL command. My FM script then created a label text file by reading PrintCommands and the other FM files that contained the product information for each label. After writing the label file I exported it to a windows directory within my FM script (tab format worked ok). If a label file already existed in that directory it was overwritten, which is what I wanted.
Next there are 2 options. You can use a free ScriptMaster plug-in to run a windows script or you can use SendEvent to send a windows command to direct the file to the printer (I used print path/filename.tab >lpt1). My Zebra printer connected to the printing station using USB so I first had to redirect the USB port to LPTx. (I used net use ...) to assign my printer to LPT1.
I saved all the parameters in a table and moved them into global fields on startup. I created the windows commands within a script and execute the script whenever labels needed to be printed. It works without any user intervention other than pressing the Print Labels button. Because I kept the ZPL commands in an FM table I was able to create a print alignment function where the user could print a test label after adjusting the width and height adjustments using up/down, left/right buttons. When it was aligned properly I saved the values back into the ^FOx,y ZPL command and updated the associated record in the PrintCommands file. It appears that alignment was only needed the first time.
The process has worked very well.