Re: Questions about proper newline handling in psql output

This has been saved for the 8.2 release:

http://momjian.postgresql.org/cgi-bin/pgpatches_hold

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Martijn van Oosterhout wrote:
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> Hi,
>
> I basically have a functional version for aligned output, examples at
> the bottom of this email. It handles multiline data values and
> multiline headers. However, there are some areas where I could use some
> input.
>
> 1. To be able to control the spacing, psql now has to be very careful
> about its output. eg \r is printed as \r, ascii control characters are
> output as \x00 style and other control chars as \u0000. This is a
> change from previous behaviour, yet you're pretty much forced to if you
> want to control the output.
>
> Is this change acceptable?
>
> 2. Currently I've changed the aligned outputs but not the unaligned
> ones. Given you're not worrying about alignment there anyway, why do
> the work? Also, we recommend unaligned output for script users so I
> don't feel right changing it.
>
> Is this distinction acceptable?
>
> 3. How to show that a value is continued? As you can see below I use
> ':' before columns that have data. This obviously doesn't work for
> first column if there's no outer border. If your border style is 0
> you're totally out of luck.
>
> I remember a discussion on this before but couldn't find it in the
> archives. Either a reference or some other hints would be appreciated.
>
> 4. Some system output like pg_views has really really long strings,
> would it be acceptable to change the output there to add newlines at
> various places to make it output nicer with this change?
>
> 5. Auto string folding. If a string is really long, fold it so it fits
> in a screen width, perhaps with '\' continuation. I havn't done this
> but I can imagine some people (including me) would love it.
>
> 6. Currently I've implemented support for UTF-8 and all ASCII
> compatable single-byte encodings. Given that psql didn't support the
> others anyway maybe no-one cares, but I have to ask: does anyone care?
> If so, I need info on *how* to support an encoding.
>
> Thanks for your attention. See you tomorrow.
>
> Query is: select oid, prosrc as "HdrLine1
> HdrLine2", proacl from pg_proc limit 1;
>
> Border style is 1.
> oid | HdrLine1 | proacl
> | HdrLine2 |
> -------+---------------------------------------------------------------------+--------
> 17009 | select 1 union all select 2 union all select 3 union all |
> : select 4 union all select 5 union all select 6 union all
> : select 7 union all select 8 union all select 9 union all
> : select 10 union all select 11 union all select 12 union all
> : select 13 union all select 14 union all select 15 union all
> : select 16 union all select 17 union all select 18 union all
> : select 19 union all select 20 union all select 21 union all
> : select 22 union all select 23 union all select 24 union all
> : select 25 union all select 26 union all select 27 union all
> : select 28 union all select 29 union all select 30 union all
> : select 31 union all select 32
> (1 row)
>
> Expanded display is on.
> -[ RECORD 1 ]-----------------------------------------------------------------
> oid | 17009
> HdrLine1 | select 1 union all select 2 union all select 3 union all
> HdrLine2 : select 4 union all select 5 union all select 6 union all
> : select 7 union all select 8 union all select 9 union all
> : select 10 union all select 11 union all select 12 union all
> : select 13 union all select 14 union all select 15 union all
> : select 16 union all select 17 union all select 18 union all
> : select 19 union all select 20 union all select 21 union all
> : select 22 union all select 23 union all select 24 union all
> : select 25 union all select 26 union all select 27 union all
> : select 28 union all select 29 union all select 30 union all
> : select 31 union all select 32
> proacl |
>
> # select chr(8);
> chr
> ------
> \x08
> (1 row)
>
>
> --
> Martijn van Oosterhout <kleptog(at)svana(dot)org> http://svana.org/kleptog/
> > Patent. n. Genius is 5% inspiration and 95% perspiration. A patent is a
> > tool for doing 5% of the work and then sitting around waiting for someone
> > else to do the other 95% so you can sue them.
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