来，试试PERL

试试，看看能否真的替代AWK,SED这些的。。。

#!/usr/bin/perl

print "hello, world!\n";

$line = <STDIN>;
if ($line eq "\n") {
    print "That was just a blank line!\n";
}else {
    print "That line of input was: $line";
}
;
) {
    ;
    print "count is now $count\n";
}

$madonna = <STDIN>;
if ( defined($madonna) ) {
    print "The input was $madonna";
} else {
    print "No input available!\n";
}