Shell script to call python program with changing arguments

Question

I have images in a sub-folder. Let's the folder images

I have a python program which will take image arguments from the folder one by one, the images are named in sequential order (1.jpg , 2.jpg, 3.jpg and so on).

The call to the program is : python prog.py 1.jpg

What will be a shell script to automate this ?

Please ask for any additional information.

• Harsha Biyani: first get all file names from folder. Run for loop for running python script for all files.
• Tanmay Bhatnagar: @HarshaBiyani sir I have no experience in writing shell scripts

Answer 1

Try this from the folder that contains images/:

for i in images/*.jpg; do python prog.py $i done

• Mark Setchell: Rather than surround blocks of code with backticks, it is easier to select the code and click the {} button in the Formatting Toolbar near Bold and Italic. Or you can put 4 spaces at the start of each line.

Answer 2

You could do them all in parallel very simply with GNU Parallel like this:

parallel python prog.py ::: images/*.jpg

Or, if your Python writes to the current directory:

cd images
parallel python prog.py ::: *.jpg

Answer 3

cd IMG_DIR
for item in [0-9]*.jpg
do
 python prog.py $item
 echo "Item processed : $item"
done

You can also pass image dir as a shellscript argument

• user1934428: Since we are talking about POSIX shell here, $item needs to get quoted when passed to python, otherwise it would break if the image name has embedded spaces.
• user1934428: Also, since the OP is only interested in jpg file names starting with a digit, the loop should read for item in [0-9]*.jpg