Open a file without its name

need some help

i have a PHP script that save reports each 30 min in CSV file

In the directory is always only 1 file(if there is already a file than script delete it and save new one each 30 min)

So,i need to open this specific CSV file with au.3

file name its a random combination of 20 character(ex:4jd#6eor93$ufie5@sd7)

file have each time random unique name