Re: [9fans] Getting started in Plan9 - help

[Mike Haertel <mike@ducky.net>]

>> If you put the command history editor in the shell, then you can only
>> use it in the shell; if you use another shell from time to time, then
>
>Not if you put it in a library and link the library
>against every single program that could ever possibly
>want to read input!

Or better yet, put it in rio.  Then every program gets the
feature, and nobody has to remember to use the funny library.

Plus, libraries have some troubles of their own..

* If static libraries, then you have to relink everything
  every time you change the library.

* If dynamic linked libraries, you have taken the first step
  on the slippery slope to the land of gratuitious complexity,
  where even a simple "hello, world" C program can execute
  100000 instructions before it actually prints anything.
  (No, I'm not kidding.)  For some reason, people seem to think
  adding features in dynamic libraries is "free".

Only problem with putting it in rio is that you don't have
quite enough information there.  To do intelligent history
and completion, you really want to know a few things like
what program you're doing it for, what their current directory
is, what their environment variables are, and so on.