Hi @NetWallah,

Thank you so much for your patience in responding to my question.

I have not tried to perform the pattern search; I thought of trying it later as I wasn't able to get the basics correct.

Actually in the program above, I was thinking of the following:

1. Read in file_list.txt which contains a list of files: a.txt, b.txt, c.txt.

2. Open file_list.txt, and then open the individual files listed in file_list.txt.

Thank you very much for your kind help! :)