Suppose I have a text file like this: 
XXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXX
XXXXXXXXXXXXaaaa
abcdefghijklm%nopqrstuvw%xyz

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What I need to do is read the file until I reach the "aaaa" at the end of the line and then change the $/ to be % instead of \n. I tried this: 
while (<FILE>) {
    if (/aaaa$/) {
        $/ = '%';
        while (<FILE>) {} # I tried it with and without this loop
    }
}

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If the second while is in there, nothing happens inside of it, and without it, the loop does not cycle back again. Any suggestions?

In reply to Changing $/ mid-file by jgallagher

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