On Fri 01 Oct 2021 at 20:53:26 (-0400), Greg Wooledge wrote:
> On Fri, Oct 01, 2021 at 05:44:41PM -0700, Fred wrote:
> > man command | col -b > command.txt
>
> Curious.
>
> unicorn:~$ man ls > ls1
> unicorn:~$ man ls | col -b > ls2
> unicorn:~$ ls -l ls1 ls2
> -rw-r--r-- 1 greg greg 8299 Oct 1 20:49 ls1
> -rw-r--r-- 1 greg greg 7745 Oct 1 20:49 ls2
>
> Glancing at the diff -u between the two files, most of the changes
> appear to be whitespace related.
>
> Opening them both in vim, the second one has a bunch of literal tab
> characters, whereas the first one has no tabs at all -- only spaces.
>
> So I guess most (or all?) of the size reduction is groups of spaces
> being replaced by tabs.
Yes, diff -ubw will confirm that whitespace is the only difference.
I'm too lazy to check that the /apparently/ significant differences
shown by diff and diff -u are merely caused by the left-margin offset,
which makes TABs skip to different columns from those intended.
Like others, I tried to guess what Gene really wanted (I can barely
believe the answer) and to come up with a suitable method. I also
tried out others' suggestions. We don't know what the mysterious
man 9 actually is (unless there's a well-known command named "9"),
so I used man man and man bash¹.
$ man man > /tmp/man.txt
$ man --ascii man > /tmp/man.txt
If you use this, and then intend to print it, have a care what the
width of your window is set to. Too narrow and you get hyphena‐
tion hell; too wide and you have to shrink it down to fit the paper.
$ man -t man > /tmp/man.txt (wrong)
$ man -t man > /tmp/man.ps
Good for people who still have a PostScript workflow.
Myself, I prefer:
$ man -t man > /tmp/scratch.ps && ps2pdf /tmp/scratch.ps /tmp/man.pdf
And if you have a big screen, you can postprocess it with, say,
$ pdfjam --vanilla --nup '2x1' --noautoscale true --scale 1 --landscape
--papersize '{11in,17in}' --outfile /tmp/man-2up.pdf /tmp/man.pdf
and have double spreads. US paper sizes. ☹
File sizes:
Not usually much of an issue nowadays. But let's see:
66546 /tmp/man.pdf
72147 /tmp/man.ps
35932 /tmp/man.txt
and col -b can reduce the size of man.txt a little.
But moving on to bash:
377528 /tmp/bash.pdf
616850 /tmp/bash.ps
345111 /tmp/bash.txt
Not such a big difference now between the text and PDF.
And I can easily close that gap by revealing what I haven't
earlier: /tmp/bash.txt was generated on a 121-wide xterm.
So, running COLUMNS=NNN man --ascii bash > /tmp/bashNNN.txt
to simulate different widths, we get:
377528 /tmp/bash.pdf
381919 /tmp/bash072.txt
371213 /tmp/bash080.txt
355442 /tmp/bash100.txt
345111 /tmp/bash121.txt
And I would finally add that reading through any of /tmp/bash*.txt is
/very/ heavy going, and difficult to absorb, because of the frequency
of special terms, which usually would be coloured or marked up.
¹ Decades ago, I used to print out big man pages, such as bash, fvwm
and ffmpeg, so that I could read through them in an armchair (no
laptop then). I still generate PDFs for those and others, as I find
the result easiest on the eye. I also find them easiest to navigate
(flicking back and forth) because the formatted pages have the most
distinguishable individual appearance.
Cheers,
David.
