So I spent the last few hours trying to figure out how to get my client-server system (which now uses sockets) to transfer files. The final results is:

For the server: 
sub SendFile
{
   my($to, $file) = @_;

   print $to "Sending $file:\n";
   open(IN, $file) || die("Could not open $file: $!\n");
   binmode(IN);
   print $to <IN>;
   print $to "\nEND\n";

   close IN;
}

[download]
and for the client: 
sub RecieveFile
{
   my($server) = $_[0];
   $line = <$server>;
   $line =~ /Sending (.*):/;
   print("Receiving $1...\n");
   open(OUT, ">$1.cpy") || die("Cannot open $1.cpy: $!\n");
   binmode(OUT);
   while(($_ = <$server>) ne "END\n")
   {
       print OUT;
   }
   close(OUT);
   print("Finished\n");
}

[download]
Originally I tried to do this without the little END tag; however that produced odd results. The client would seem to hang until the server was killed, at which point the client would recieve the file. Because I didn't know whether this one was should happen or not, I wrote the following test program: 
use strict;

open(IN, $ARGV[0]);
binmode(IN);
open(OUT, ">$ARGV[0].cpy");
binmode(OUT);

print OUT <IN>;

close(OUT);
close(IN);

[download]
This program copies the file specified in its first agrument. Moreover this program works perfectly. Then I guessed that maybe (due to the client-server system) there was no way to specify that I had finished sending the binary output, so I added a newline character where the END tag currently is. That had the unfortunate result of sending will more then triple the actual file size to the program. Thus I came up with the END tag you see here.

My question is: "Why did that stuff happen?" Am I missing some fundamental concept?

Thanks,
Boots

In reply to client server file transfer by Boots111

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