You want don't want to use eq and a pattern. Use something like this instead...

for (1..10) {
    ...
    last if ($charread =~ /\s/);
}
[download]

or

for (1..10) {
    ...
    last if ($charread eq " " || $charread eq "\t" ....);
}
[download]

Update: Reread the supplied code :)

Update 2: replace $_ with $charread.