Migrtaion, bison has no option -P like yacc

[Ramnarayan.Gupta]

Hello,
       Appreciate your help for this in advance. Yacc used to have an option 
called -P to pass custom parser (Allows you to specify the parser of your 
choice instead of /usr/share/lib/ccs/yaccpar. For example, you can specify). 
Our code currently using that feature whicn needs to be migrated over to bison 
which doesn't have this option. Any idea about the approach?
Rgds
Ram