How can a source be defined from a usrbin output file

Dear experts,
I installed the latest Flair(3.1-13) and Fluka(4.1-1), and was recently running a shelding problem. I want to use the function which defines the source from a usrbin output file. I can’t find any reference about it. So could you give me an example, or some reference which I could follow?
The function mentioned here, Download latest FLUKA release | The official CERN FLUKA website.

 Best regards,

yours Jiangfeng

Dear @wan,

I suggest you to have a look at the manual for the SPECSOUR card, particularly at the BIN-SOUR SDUM

Additionally, you can have a look at this post, specifically at point 2.5.

Dear amario,
Great thanks for your kind help. It did help me.

Best regards,