Hi monks, I would like to seek advice on how to deal with parsing binary data file.

The binary file contains variable length records. (tag-length-value) Some variable-length-records are optional and appear at the end of a record. In that case, the optional field (length) itself is not in record. e.g 

     integer,character,variable string,optional variable string

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Variable string is length encoded string. length follow by content.

How do I use unpack in this case? Since I need to know how many bytes are consumed by unpacking of required fields?

In reply to perl pack/unpack optional variable length data by bagyi

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