Instead, you might want to try something like

local $/ = '****';
my @whole = <FILEHANDLE>;
print NEWFILE pop @whole; #you might want to stick it in a temp scalar
+ first to make it clearer... some people think print() with side effe
+cts is unclear
print OLDFILE @whole;
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updated note: you don't have to use an array to do it this way, if you needed to actually process some of the input before all the input is received... you can do the same thing with a loop, but it's messy, because you'll be wanting to process the value you got on the _previous_ iteration, then process the last one outside the loop. You could also use sysread instead of <>, which will let you safely play with seeking and looking ahead for EOF, but unless you really really really need to do it that way, it's Bad News.
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