While loop to test if a file exists in bash

Question

I\'m working on a shell script that does certain changes on a txt file only if it does exist, however this test loop doesn\'t work, I wonder why? Thank you!

Answer 1

I ran into a similar issue and it lead me here so I just wanted to leave my solution for anyone who experiences the same.

I found that if I ran cat /tmp/list.txt the file would be empty, even though I was certain that there were contents being placed immediately in the file. Turns out if I put a sleep 1; just before the cat /tmp/list.txt it worked as expected. There must have been a delay between the time the file was created and the time it was written, or something along those lines.

My final code:

while [ ! -f /tmp/list.txt ];
do
    sleep 1;
done;
sleep 1;
cat /tmp/list.txt;

Hope this helps save someone a frustrating half hour!