[TriLUG] colorize stderr in bash

[Brian Phelps]

On Wed, 2008-07-23 at 17:40 -0400, Andrew Ball wrote:
> I wonder if there's a way to pipe stderr to a program that adds
> escape sequences and sends it right back to stderr while
> leaving stdout intact.
I actully know how to do this with sed, I just need to figure out how to
do this interactively with .bashrc

> 
> 
> On Wed, Jul 23, 2008 at 5:37 PM, Brian Phelps <brphelps at ieee.org> wrote:
> > Thats interesting, not worried about doing it with files or certain
> > commands, I think I can figure out how to do that with sed.
> >
> > I guess I'm looking for the short quick answer to "What line can I add
> > to .bashrc to get colorized stderr"
> >
> > I found one for zcsh, but I don't know how to get my shell, bash to do
> > something similar when I log in interactively.
> >
> >
> > On Wed, 2008-07-23 at 17:19 -0400, Kevin Hunter wrote:
> >> At 4:28p -0400 on Wed, 23 Jul 2008, Brian Phelps wrote:
> >> > Is there an easy way to colorize stderr in an interactive bash shell?
> >>
> >> Obligatory disclaimer: be wary of using colors in the terminal.  Not all
> >> terminals/emulators are created equal, nor are ANSI escape sequences
> >> portable.  Colorized output that looks absolutely splendid on one
> >> author's machine may be barely readable on another's.  (e.g. Yellow text
> >> on black, and white backgrounds.)  Also, be aware that a significant
> >> portion of the population is colorblind, and for which colors have the
> >> opposite effect they might have for you.
> >>
> >> Long answer:
> >>
> >> That said, I prefer colors and think they're currently underutilized in
> >> the industry.  For those who *aren't* color blind, and who use ANSI
> >> capable terminals emulators colors can help identify breaks in longs
> >> scrolls of largely superfluous output text, or bring out warning or
> >> error messages.  For example, a tail of a web log and highlighting 404s
> >> (NOT FOUND), or 500s (SERVER ERROR)*, or parsing debug, informational,
> >> and warning messages from a compiler, or running program.  Some folks
> >> even colorize their command prompt.
> >>
> >> Examples of programs in the wild that colorize (some) of their output
> >> django, pulseaudio.  I have found that the lightred lines move my eye
> >> directly where they need to be, and now I know what they mean; I don't
> >> have to reread them everytime to know what's up.
> >>
> >> If you're worried about portability and playing-nice-with-others, I
> >> would caution you to make an *easy* opt-in or opt-out preference for
> >> those who do(n't) want colors.
> >>
> >> Short answer: the same way you'd do it with stdout: with escapes.
> >>
> > How do I get the shell to do it interactively?
> >
> >> Some projects you might want to peruse:
> >>
> >> http://scriptechocolor.sourceforge.net/
> >> http://www.scribd.com/doc/2099456/Advanced-BashScripting-Guide
> >>
> >> Kevin
> >>
> >> * Obviously, you don't want to clutter the logs with escape sequences,
> >> but what about piping to another program, e.g.
> >>    $ tail -f log | http-colorizer
> > --
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> >
> > --
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> >
> 
> 
> 
> -- 
> =======================
> Andrew D. Ball
> 勃安
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