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Re: tn3270, mset and map3270


We discussed termcap versus terminfo issue many years ago,
and we selected termcap since it is more flexible.
termcap allows users to use local capabilities
(not defined by standard) naturally,
but terminfo doesn't have portable way to do that.

Please use termcap at least in the base system.

So, the ways to go are one of following three:

1. have termcap and terminfo libraries/databases separately
   This is what most operating systems do.

   This is easy to implement, but requires duplicated databases
   for termcap and terminfo.
   This is somewhat awkward, but most people know termcap flexibility
   can't be realized by terminfo.

2. implement terminfo as an emulation on termcap
   This is what I proposed in the previous article.

   In the past, terminfo was faster than old termcap that linearly
   looked up text database, but our new termcap uses hashed database and
   the speed is comparable to terminfo.
   Converting termcap capabilities for terminfo library is well defined,
   and this should be easy to implement.
   This will be the most compact in size since it uses only one database.

3. implement termcap as an emulation on terminfo
   I'm afraid but I don't think this is a good idea.

   To implement termcap flexibility, the termcap capabilities
   should be stored literally into terminfo database,
   which duplicates databases eventually.

I prefer 2, but 1 will be accepted.
I don't think we need to go to 3, the most difficult.

ITOH Yasufumi

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