How to get the process id of a bash subprocess on command line

Question

I know in bash we can create subshells using round parenthesis ( and ). As per bash man page:

(list) list  is  executed  in  a  subs         


        

Answer 1

This seems like it works:

(echo $$; echo  `ps axo pid,command,args | grep "$$" |awk '{ getline;print $1}'`)
14609
17365

For whatever reason, OSX is limited and doesnt come with pgrep, or one could do (which works in Linux):

 (echo $$; echo  `pgrep -P $$`) 
 14609
 17390