Blank fields are not recognized.

## Background [Optional]
Hello
when I parse data file with cobirx, the data file and copybook was not match, if there is a null or empty,the data file does not retain space,and the following column was move backward .there is a column name data length,I use this record fixed length option ,when comes to position 40 there is incorrect values.any suggestions to solve null value was not retain space issues?

## Question
if there is no space or null character in hex, can I parse data file with cobrix?

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