changing env variables of another sessions
is there a way of how to force changnig env variables to someone else's running shell? My situation is like this: on a jump box I've increased HISTSIZE and HISTFILESIZE in bash profile to the generic jump user, but it won't propagate to already running shells, which, upon exiting, would shrink all the history to the original little lenght which obviously I don't want.
One way is simply sending a SPAM to all the logged in people to manually change their session variables and I might end up that way but I am wondering if that couldn't be done more elegantly... So far, I was unable to find anything on Google.
I know I can read /proc/[PID]/environ but can I write to it? (most definitely not by using awk and/or sed etc. to change the variable values in-line).
Assume I have full root, of course...
Thanks a lot,