In a bash script, how to get the display width of a string

Question

I need a bash function to count the line width that will be displayed when displayed. because in my cases the string may contain some widescreen (for example, Chinese). So I can’t just use the length of the string.

function getDisplayWidth () { ??? } 

Then "abc" will return 3 and "前后" should return 4 instead of 2.

Answer 1

If your wc implementation has the -L option, that means counting the correct “thing”. (Coreutils has this, not sure what others are doing.)

Example:

 $ getw() { wc -L <<< "$1"; } $ getw 前后4 $ getw 前a后c 6 $ getw abc前后7 $ getw "行书 / 行書" 11 

Answer 2

Try wc -m . On the os x help page:

The number of characters in each input file is written to standard output. If the current language does not support multibyte characters, this is equivalent to the -c option. This will invalidate any previous use of the -c option.