Multiple bash script with different parameters - bash

Question

I have the following bash script, that I launch using the terminal.
dataset_dir='/home/super/datasets/Carpets_identification/data'
dest_dir='/home/super/datasets/Carpets_identification/augmented-data'
# if dest_dir does not exist -> create it
if [ ! -d ${dest_dir} ]; then
mkdir ${dest_dir}
fi
# for all folder of the dataset
for folder in ${dataset_dir}/*; do
curr_folder="${folder##*/}"
echo "Processing $curr_folder category"
# get all files
for item in ${folder}/*; do
# if the class dir in dest_dir does not exist -> create it
if [ ! -d ${dest_dir}/${curr_folder} ]; then
mkdir ${dest_dir}/${curr_folder}
fi
# for each file
if [ -f ${item} ]; then
# echo ${item}
filename=$(basename "$item")
extension="${filename##*.}"
filename=`readlink -e ${item}`
# get a certain number of patches
for i in {1..100}
do
python cropper.py ${filename} ${i} ${dest_dir}
done
fi
done
done
Given that it needs at least an hour to process all the files.
What happens if I change the '100' with '1000' in the last for loop and launch another instance of the same script?
Will the first process count to 1000 or will continue to count to 100?

Answer 1

I think the file will be readonly when a bash process executes it. But you can force the change. The already running process will count to its original value, 100.
You have to take care about the results. You are writing in the same output directory and have to expect side effects.

Answer 2

"When you make changes to your script, you make the changes on the disk(hard disk- the permanent storage); when you execute the script, the script is loaded to your memory(RAM).
(see https://askubuntu.com/questions/484111/can-i-modify-a-bash-script-sh-file-while-it-is-running )
BUT "You'll notice that the file is being read in at 8KB increments, so Bash and other shells will likely not load a file in its entirety, rather they read them in in blocks."
(see https://unix.stackexchange.com/questions/121013/how-does-linux-deal-with-shell-scripts )
So, in your case, all your script is loaded in the RAM memory by the script interpretor, and then executed. Meaning that if you change the value, then execute it again, the first instance will still have the "old" value.