Can Blat be used when name of the attached file is unknown?

We have a POS Program that creates .txt Files with sales results at the End of Day Routine. These Files have names like Print2070602.txt. 
I would like to see if we can send Emails with Blat by pointing to the directory, f.i. C:\POS\PrintFIles\ with some kind of a Wildcard (*.txt). Looks like this is not supported. Any idea how to succeed?

The command line blat :C\POS\Printfiles\*.txt results in 'unknown error code 123 when trying to open C:\POS\PrintFiles\*.txt