change ulimit fsize permanantly

Hi,
on HP-UX when I run command
ulimit -a
I get

time(seconds) 4096
file(blocks) unlimited
data(kbytes) 1048576
stack(kbytes) 8192
memory(kbytes) unlimited
coredump(blocks) 4194303
nofiles(descriptors) 4096

Now I want to change
file(blocks) unlimited
to file(blocks) 50MB

Can anyone help me to change it?

# ulimit UL_SETFSIZE <>

Better, you can do

#man ulimit and get detailed information before you proceed changing.

-DB

Thank you for your reply.
I tried with the same, but it didnt change the fsize permanantly, in another console it is showing me unlimited. And I want to make it less than 1GB.