Unexpected padding behavior with printf

Question

I'm trying to pad spaces onto a series of strings in bash, using the printf suggestions outlined here and here.

Iterating over test characters...

for i in a b c d e f g
do
  printf "%-7s" "$i"
done

...produces expected results:

a      b      c      d      e      f      g

But iterating over the actual strings produces strange results:

for i in date sha percent total covered uncovered
do
  printf "%-7s" "$i"
done

date   sha    percenttotal  covereduncovered

Why do those two iterations result in different spacing?

The shell's `printf` command has the useful feature of *repeating* tbe format until it runs out of arguments. So you don't need the`for` loop. You can just do `printf '%-7s' date sha percent total covered uncovered`. — rici, Jun 12 '17 at 04:08

score 2 · Accepted Answer · answered Jun 12 '17 at 01:06

2

Padding only adds spaces to bring the total width up to 7. percent and covered, though, already have 7 characters, so no padding is necessary after either string.

answered Jun 12 '17 at 01:06

chepner

497,756
71
530
681

score 0 · Answer 2 · answered Jun 12 '17 at 01:25

Is this what you want?

$ for i in date sha percent total covered uncovered; do
>   printf "%-7s%-6s" "$i" ""
> done
date         sha          percent      total        covered      uncovered      $

(Notice that my prompt is at the end of that string.)

Unexpected padding behavior with printf

2 Answers2