> I don't see how this can be helped other than keeping buffers allocated
> on a per open-file basis — and that would be overkill.
We run an embdeed os at work for which we stole many ideas from plan9.
It has a lib9pfile like library to make writing servers easier.
Generally it uses an array of initialised C structures to define the
hierarchy you want to serve, which contains functions to generate the
contents of these files; Each file also has an associated read and write
flag word. Files can be read:
line at a time - the library assembles the lines into the
requested buffer's worth
file at a time - contents generated in malloced memory on open
and freed on close
raw access - requests passed direct to underlying function
writing files can be flagged smilarly:
line at a time - newlines and leading and trailing whitespace stripped
file at a time - application specific function called only on close
raw - as above.
This has been useful and I have thought about writing a similar library for
plan9 but have not done so yet, its difficult to decide what is useful often
enough to libraryise and what is just "nice to have".
-Steve
