Dear derekludwig,
read all lines of the entire file at once was my goal.
I had tried this command tr, but in wrong way I see, because you have written < test.txt > test2.txt, not me (I had just written test.txt > test2.txt).
And I haven't tried to use Perl language because is again another form of coding for me.
Your answer is very good, I have tested it, and it is very fast.
So, thank you again for your answer and your easy understanding of my problem.
I'm a PhD student (french), I had this problem since Monday. Thanks to you, I can perform my work this night, and forget this nightmare. I need to send the result of my work before the end of the next week. Thanks to you, I'm able to make it.
So, really, thank you so much.
Have a good evening !!
Hope to don't disturb you again before midnight !
Bye.