$foo= '\t\a\b\c';
print "foo=($foo)\n";
quotemeta $foo;
print "foo=($foo)\n";
$foo= quotemeta $foo;
print "foo=($foo)\n";
__END__
Produces:
foo=(\t\a\b\c)
foo=(\t\a\b\c)
foo=(\\t\\a\\b\\c)