How to loop through yesterday's files

Hello Gurus,

I want to loop through a folder that contains multiple files with different dates like

test061113RELAYPHYS_1053353896_01.txt

test061013RELAYPHYS_1053353896_01.txt

test060913RELAYPHYS_1053353896_01.txt

Now I only want to send the file with yesterday time stamp in it. How can I do that without using .net.

Please help me with this.