Loop over files (Bash)
This is cool: You can loop over files in a directory and do stuff with it!
Examples
Start simple
#!/bin/bash cd ~/images-tmp for file in * do echo "File name: $file" done
Operate on each file
Create links to all files in this folder, and put those links in another folder:
for file in *.jpg
do
source="${PWD}/${file}"
link="/var/www/media.example.com/tmp2/$file"
echo " Path+file: $source - Destination: $link"
ln -s "$source" "$link"
done
Complete example including shopt
I've seen the shopt statements in examples from others. I guess it stands for shell option. Turned out I really need them. And yes: This is not the most elegant or efficient script. It works.
#!/bin/bash
# Populate directory "all-product-images"
################################################################################
#
# * Use this script to populate directory "all-product-images" with links to
# the actual images elsewhere
# * This script is repeatable: Added new images? Just add the path in the script
# below, and run the script again
# * "ln" doesn't overwrite existing links. That makes this script repeateable
# * Maybe start with the most relevant directories?
# * Have just one directory, called "all-product-images" - Don't distinguish
# between "with-logo", "without-logo", etc.: That makes it just much more
# work
# * Source: https://wiki.devliegendebrigade.nl/Loop_over_files_(Bash)
#
#
# History
########################################
#
# * 2022.08.08: Created: There was a need for a directory with all images
# without logos
#
#
################################################################################
# create_all_links_from_directory()
################################################################################
#
create_all_links_from_directory()
{
#
# First loop for .jpg
#
for file in *.jpg
do
source="${PWD}/${file}"
link="${root}all-product-images/$file"
echo " Source: $source Link: $link"
ln -s "$source" "$link"
done
# Second loop for .png
#
for file in *.png
do
source="${PWD}/${file}"
link="${root}all-product-images/$file"
echo " Source: $source Link: $link"
ln -s "$source" "$link"
done
}
################################################################################
# Loop through directories
################################################################################
#
# From most to least relevant?
########################################
#
# * It seems like nitpicking, but there actually are some cases where the
# overall quality is better when doing this in the right order: Do
# "without logo" before "with logo"
#
#
# Start here
########################################
#
root="/var/www/media.example.com/"
shopt -s extglob
shopt -s nullglob
cd ${root}custom-jpg-without-logo; create_all_links_from_directory
cd ${root}custom-jpg-logo; create_all_links_from_directory
cd ${root}tools-jpg-without-logo; create_all_links_from_directory
cd ${root}tools-jpg-logo; create_all_links_from_directory
cd ${root}misc-jpg-without-logo; create_all_links_from_directory
cd ${root}misc-jpg-logo; create_all_links_from_directory
cd ${root}promotion-jpg-without-logo; create_all_links_from_directory
cd ${root}promotion-jpg-logo; create_all_links_from_directory