This utility is used to extract the VBA project binary from an Excel 2007+ xlsm file. The VBA project can then be added to an Excel::Writer::XLSX file to enable it to have macros.
An xlsm file is a version of an Excel xlsx file that contains an additional VBA project binary file. The xlsm file format is a collection of mainly XML files in a ZIP container.
The extracted VBA project is an OLE Compound Document in binary format. It is named vbaProject.bin and is generally located in the xl directory of the xlsm file.
See the add_vba_project() section of the Excel::Writer::XLSX documentation for more details.
Note: you can also extract the VBA project from an xlsm file using the standard Linux unzip command:
unzip -j macro01.xlsm xl/vbaProject.bin
On Windows you can use any suitable Unzip application.