filetest.pl

#!/usr/local/bin/perl
use strict;
use warnings;

my $target;
while(1){
	print"What file should I write on?" ;
	$target = <STDIN>;
	chomp $target;
		if(-d $target){
			print"No, $target is a directory!\n";
			next;
		}
		if(-e $target ){
			print"File already exists. What should I do?\n";
			print"(Enter 'r' to write to a different name, ";
			print "'o' to overwrite or\n";
			print "'b' to back up to $target.old)\n";
			my $choice = <STDIN>;
			chomp $choice;
			if($choice eq 'r'){
				next; 
			}elsif($choice eq 'o'){
				unless(-o $target){
					print"Can't overwrite $target, it's not yours!\n";
					next;	
				}	
				unless(-w $target){
					print"Can't overwrite $target:$!\n";
				}
			}elsif($choice eq 'b'){
				if(rename($target, $target." .old")){
					print"OK, moved $target to $target.old\n";
				}else{
					print"Couldn't rename file: $!\n";
					next;
				}
			}else{
				print"I didn't understand that answer.\n";
				next;
			}

	}	
	last if open OUTPUT, ">$target";
	print"I couldn't write on $target: $!\n";


}
print OUTPUT "Congratulations.\n";
print "Wrote to file $target\n";