I suspect you are confused because your final print statement emits something like $VAR1 = 'GLOB(0x817f880)'. As for why:

• You never set the global separator to "//". You merely defined it to nothing at all. To set the record separator to "//", you do local $/='//'. That will break your input stream into records ending with '//'.
• You never read in your file. Your split statement is attempting to split the string representation of an input handle, i.e. 'GLOB(...)', not the contents of your inputfile. To read a file into an array you need to use <$in>. To remove the '//' from the end you need to use chomp.

Your code should look something like this if you want to read in everything in one gulp:

local $/='//';        #define record separator
my @records = <$in>;  # read in all records
chomp @records;       #get rid of trailing // from each record
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Or this, which reads in one record at a time and is much more memory efficient

local $/='//';
while (my $record = <$in>) {
  chomp $record;   #remove // from end of line
  #... process the record ...
}
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