[Question] Can someone provide the explain of the relation between PGPROC and transaction?

Hi Community!

I have already read the comment of the proc.h, read some related question about it, and read the "74. Transaction Processing" of the PostgreSQL document.

But I really don't know how the PGPROC works in the transcation?

Can someone provide me some help? Thanks in advance!

Yours,

Wen Yi.