Your problem is that the "ls -1" system call returns your directory names with a newline character ("\n") appended and you're not removing that character before attempting to open the file. Add a chomp:

if($file=~/^\d/)
{
   chomp $file;
   $dlist[$x]=$file;
}
[download]

That being said, you should also:

• use strict; and use warnings; at the top of your script
• use a lexical variable for the filehandle and the three-argument form of open: open (my $fh,"<","$path1/build.log")or die "$!\n";
• Use the perl inbuilt functions (opendir,readdir) for reading directory contents instead of ls
• Consider using File::Find or File::Find::Rule for locating the files you want to handle