colourize crontab -l

with

crontab -l

comments are shown with an ugly yellow background.

can the output colours be customized?

Thanks

Originally Posted by jt1122 with crontab -l comments are shown with an ugly yellow background. can the output colours be customized? Thanks

Almost everything can be customized, if one is willing to work at researching how.
I might start with saying that you can STRIP color by filtering through something that does not color. Example:

crontab -l | cat

For more than that we might need to know what shell you are using, in what terminal program, under what version and release of which distribution of Linux, and a few other details.

Thanks.

Using Debian Testing + bash 5.2.21(1) .

That narrows it down to one of (I think) 14 terminal emulation terminal programs depending upon what GUI (if any) you might have chosen to install. For each there are also multiple settings and environment variables that might impact colors in display. Several of them allow you to specifically set the colors, hue and saturation, for multiple classes of foreground, background highlighting, bold, etc. Have you looked for settings information in the man page for your specific terminal program?

It looks like it's the feature of crontab:

Originally Posted by man crontab The -l option causes the current crontab to be displayed on standard output. When the output is a tty, comment lines are colored to distinguish them from action lines.

How to prevent crontab from displaying the colored comments?

Originally Posted by morfik How to prevent crontab from displaying the colored comments?

...or customize the colour being used for comments.

Originally Posted by morfik It looks like it's the feature of crontab: How to prevent crontab from displaying the colored comments?

See #2. Pipe through cat (or anything else) and the STDOUT for the command is the pipe, not a tty, so it does not color.

Also, if you change the terminal type to one that does not support color for that command you will get no color.

If it is the same ls that I use, try

ls --color=never

I think I'll wait for the support of the NO_COLOR var in cron:

Release 1.5.7 ... crontab: switch off colors if NO_COLOR is set

Originally Posted by morfik It looks like it's the feature of crontab: How to prevent crontab from displaying the colored comments?

use something like

crontab -l | grep -v "#"

since all the comments should have the '#' at the beginning of the line

ITYM

crontab -l | grep -v "^#"

to skip just the crontab comments (and not shell commands with a #).
But I prefer to only prevent the coloring, as already suggested:

crontab -l | cat

Originally Posted by morfik It looks like it's the feature of crontab: The -l option causes the current crontab to be displayed on standard output. When the output is a tty, comment lines are colored to distinguish them from action lines. How to prevent crontab from displaying the colored comments?

You need to read a bit further:

When listing a crontab on a terminal the output will be colorized unless an environment variable NO_COLOR is set.

But probably it depends on the exact version of the tool. Using pipe (like crontab -l | cat) will solve it too.

Note that environment variables CAN be set IN the crontab file almost as if it were a script, and they will exist and have effect ONLY during the cron run that uses that crontab file and ONLY for that crontab file's processes.

Originally Posted by jt1122 Thanks. Using Debian Testing + bash 5.2.21(1) .

Seems like this is a Debianism. For what it's worth, "crontab -l" produces simple text output on OpenSUSE; no colored comments. And no environment variables needed either.

Unless you really need to see the comments, perhaps you could define an alias that executes "crontab -l | grep -v '#'" or piping the output to cat as computersavvy suggested.