The first method I described--read the entire block, and then extract the header, records and trailer from it--would look something like this:
while( read DATA, $data, BLOCKLEN ) {
## Extract the header from the front of the block
my $header = substr $data, 0, BLOCKHDR, '';
## do stuff with $header
for my $cdr ( 1 .. MAXRECORD ) {
## Extract each record in turn from $data
my $record = substr $data, 0, CDRLEN, '';
## do stuff with $record
}
my $trailer = $data; ## Anything left in $data should be your trai
+ler.
## do something with it.
}
The second method I described might be done something like this:
until( eof DATA ) {
read DATA, my $header, BLOCKHDR or die;
## Do stuff with $header;
for my $cdr ( 1 .. MAXRECORD ) {
read DATA, my $record, CDRLEN or die;
## Do stuff with $record
}
read DATA, my $trailer, BLOCKTRL or die;
## Do stuff with $trailer
}
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
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