$COLUMNS aren't set

[yokmp]

I know, it's not rly a problem. But before you can use anything like

Code: Select all

printf "%*s\n" $(((${#TEXT} + $COLUMNS)/2)) "$TEXT"

to center some Text in your .bashrc, you must do an

Code: Select all

export COLUMNS

Else the variable is unset/empty. AFTER the Terminal is loaded (or you're logged in and see your PS1) the COLUMNS variable is set. This is since Sabayon 4 or 5. Not shure about this. Its just annoying.
So if you know a better solution than export this in the .bashrc, please tell me.

[svantoviit]

Use tput in your script: BashFAQ/091: I'm trying to get the number of columns or lines of my terminal but the variables COLUMNS / LINES are always empty.

Here is a working example (after correcting your small typo):

Code: Select all

#!/bin/bash
TEXT="TEXT"
COLUMNS=$(tput cols)
printf "%*s\n" $(((${#TEXT} + $COLUMNS)/2)) "$TEXT"

[yokmp]

Which typo? ^^
I know about tput but why use a programm when the Information should be in a global var? Plus the fact that not every Distro has tput onboard. So you have to catch that case and provide a fallback or just don't use tput and use the global. Sabayon is (as far as i know) the only Distro where its not set.
It's my personal fallback in Sabayon and a reason to switch to some exotic linux alpha

[svantoviit]

Which typo?

In the original post you wrote:

Code: Select all

$#{TEXT}

instead of

Code: Select all

${#TEXT}

I see you've edited it.

the Information should be in a global var?

It is set in an interactive shell, that's the way it works… just read the link I posted above.

not every Distro has tput onboard

It's part of ncurses which is a pretty standard package.

Sabayon is (as far as i know) the only Distro where its not set.

Sure? Don't think so.

So you have to catch that case and provide a fallback

Don't fool yourself and others

… you are welcome!

[yokmp]

[quote]It is set in an interactive shell, that's the way it works[/quote
Yes it is, and the script is only called when the shell is interactive:

Code: Select all

if [[ $- == *i* ]]; then # if interactive, then
  export COLUMNS=80 # workaround
  source ~/script.sh
fi

I would like to know is WHY it worked a while back (maybe 2 years? not shure about this)?
I mean there must be a reason they've changed it. If I can't break anything i would like to write the 'export line' in /etc/skel/.bashrc (?)