Bash For-Loop on Directories

Question

Quick Background:

$ ls src
file1  file2  dir1  dir2  dir3

Script:

#!/bin/bash

for i in src/* ; do
  if [ -d "$i" ]; then
    echo "$i"
  fi
done

Output:

src/dir1
src/dir2
src/dir3

However, I want it to read:

dir1
dir2
dir3

Now I realize I could sed/awk the output to remove "src/" however I am curious to know if there is a better way of going about this. Perhaps using a find + while-loop instead.

Answer 1

Do this instead for the echo line:

 echo $(basename "$i")

Answer 2

Use basename as:

if [ -d "$i" ]; then
    basename "$i"
fi

Answer 3

No need for forking an external process:

echo "${i##*/}"

It uses the “remove the longest matching prefix” parameter expansion. The */ is the pattern, so it will delete everything from the beginning of the string up to and including the last slash. If there is no slash in the value of $i, then it is the same as "$i".

This particular parameter expansion is specified in POSIX and is part of the legacy of the original Bourne shell. It is supported in all Bourne-like shells (sh, ash, dash, ksh, bash, zsh, etc.). Many of the feature-rich shells (e.g. ksh, bash, and zsh) have other expansions that can handle even more without involving external processes.

Answer 4

If you do a cd at the start of the script, it should be reverted when the script exits.

#!/bin/bash

cd src
for i in * ; do
  if [ -d "$i" ]; then
    echo "$i"
  fi
done