printf -vl "%${COLUMNS:-`tput cols 2>&-||echo 80`}s\n" && echo ${l// /-};

Print a row of characters the width of terminal

Unlike other methods that use pipes and exec software like tr or sed or subshells, this is an extremely fast way to print a line and will always be able to detect the terminal width or else defaults to 80. It uses bash builtins for printf and echo and works with printf that supports the non-POSIX `-v` option to store result to var instead of printing to stdout. Here it is in a function that lets you change the line character to use and the length with args, it also supports color escape sequences with the echo -e option. function L() { local l=; builtin printf -vl "%${2:-${COLUMNS:-`tput cols 2>&-||echo 80`}}s\n" && echo -e "${l// /${1:-=}}"; } With color: L "`tput setaf 3`=" 1. Use printf to store n space chars followed by a newline to an environment variable "l" where n is local environment variable from $COLUMNS if set, else it will use `tput cols` and if that fails it will default to 80. 2. If printf succeeds then echo `$l` that contains the chars, replacing all blank spaces with "-" (can be changed to anything you want). From: http://www.askapache.com/linux/bash_profile-functions-advanced-shell.html http://www.askapache.com/linux/bash-power-prompt.html
Sample Output
$ L '<' 40
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

$ L '=';
================================================================================

$ L 'x';
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

$ L '-';
--------------------------------------------------------------------------------

$ L '~';
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

$ L '`';
````````````````````````````````````````````````````````````````````````````````

$ L '>';
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

$ L '#';
################################################################################

$ L '@';
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@

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