Here is what I get using -N and -H options for sqsh:
$ sqsh -b -Usa -SLAVA64 -w132 -N N_Option -H H_Option -C "select hostname,program_name,clienthostname,clientapplname from master..sysprocesses where spid = @@spid"
Password:
hostname program_name clienthostname clientapplname
------------------------------ ------------------------------ ------------------------------ ------------------------------
H_Option N_Option
(1 row affected)
So, sqsh -N option is same as isql --appname option
and sqsh -H option is same as isql -H option