[net.unix-wizards] instability in Berkeley versus

preece@ccvaxa.UUCP (08/08/85)

> > ps: K&P on this topic suggest using "pr" as a columnising filter.
> > To my mind, "pr" is a paginator, its just as bad to make a paginator
> > produce columns as some side effect as it is to make a directory
> > listing program produce columns as a side effect - but of course,
> > this was in "pr" from the beginning, so it is blessed...

> It seems to me that a program for paginating might have to worry about
> columns, but, yes this is probably not the best place to put a
> columnator.  On the other hand, it is possible to use the columnator
> from pr from other programs, where with ls it's at very least kind of
> difficult (create a file with the name of each line, do a ls -Cf, and
> hope that there aren't two files with the same name? :-)
----------
How can you separate columnising from paginating?  Clearly you can't
columnise first, then page (you'd like the right column of a page
to follow from the left column, not from the bottom of the left
column of the last page).  Nor can you page first, then columnise.
You need a global process that alternates between grabbing enough
material for one page and formatting it for display.  That requires
either a more complicated shell than Unix has or that the processes
be turned into one program.  It might be possible to embed the
global knowledge in a shell script, but it would be a real pain.
I think this is an example of something that is best done as a
program.

I tend to agree that ls should NOT do columnising for this same reason.
Its columnising is wrong for pagination (it has to assume an
infinite page length).

-- 
scott preece
gould/csd - urbana
ihnp4!uiucdcs!ccvaxa!preece