This is in addition to what thelenm already said.

{
   local $/ = ".ENDS\n";
}
while (<SCH>){
  # ...
}
[download]

I see where you are going with this - good idea.
However, the value of $/ will be changed back to "\n" right before the while() loop and you'll end up reading the file line-by-line.
To fix, enclose the whole while loop in the same block as the "local $/;"

{
  local $/ = ".ENDS\n";
  while (<SCH>){
    # ...
  }
}
[download]

--perlplexer