Hello

This has been discussed several times on the Monastery. My favorite Way To Do It is merlyn's (and some others', of course :) :

@ARGV = ($new);
undef $/;
$^I = ".bak";
while (<>)
{
    s/66/$goodrow->{'ClientID'}/g;
    s/0906\s406\s2427/$SIMCard/g; 
    print;
}
[download]

Your file will be modified "in place", and the old data will be saved in $new.bak
All the dirty stuff is made for you by Perl ...
HTH

--
zejames