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Print a row of characters across the terminal. Uses tput to establish the current terminal width, and generates a line of characters just long enough to cross it. In the example '#' is used.
It's possible to use a repeating sequence by dividing the columns by the number of characters in the sequence like this:
seq -s'~-' 0 $(( $(tput cols) /2 )) | tr -d '[:digit:]'
or
seq -s'-~?' 0 $(( $(tput cols) /3 )) | tr -d '[:digit:]'
You will lose chararacters at the end if the length isn't cleanly divisible.
There are 8 alternatives - vote for the best!
Pure Bash
This will print a row of characters the width of the screen without using any external executables. In some cases, COLUMNS may not be set. Here is an alternative that uses tput to generate a default if that's the case. And it still avoids using tr.
printf -v row "%${COLUMNS:-$(tput cols)}s"; echo ${row// /#}
The only disadvantage to either one is that they create a variable.
One of the first functions programmers learn is how to print a line. This is my 100% bash builtin function to do it, which makes it as optimal as a function can be. The COLUMNS environment variable is also set by bash (including bash resetting its value when you resize your term) so its very efficient. I like pretty-output in my shells and have experimented with several ways to output a line the width of the screen using a minimal amount of code. This is like version 9,000 lol.
This function is what I use, though when using colors or other terminal features I create separate functions that call this one, since this is the lowest level type of function. It might be better named printl(), but since I use it so much it's more optimal to have the name contain less chars (both for my programming and for the internal workings).
If you do use terminal escapes this will reset to default.
tput sgr0
For implementation ideas, check my
http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html
function for .bash_aliases that prints a line of the character of your choice in the color of your choice across the terminal.
Default character is "=", default color is white.
For BSD-based systems, including OS X, that don't have seq.
This version provides a default using tput in case $COLUMNS is not set:
jot -b '#' -s '' ${COLUMNS:-$(tput cols)}
If you can do better, submit your command here.
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