How to check the existence of specific file names and exit statuses? (and if unsuccessful loop until successful)

Question

I'm a bash scripting rookie and have been googling this scenario for about six hours to no avail. I have found segments of what I need but no comprehensive solution.

Here is the problem: I need to write some code that will be able to check that 3 files exist (file1.txt, file2.csv and file3.log). Before proceeding however, I need to confirm that file3.log has stopped writing (this is to confirm that the script that creates the 3 files has finished successfully).

checking the existence of these files seems easy enough using something like:

if [ -f -e /path/to/file/file1.txt && /path/to/file/file2.csv && /path/to/file/file3.log]
then
# somehow check the exit status of file3.log
if [$? !=0]
#somehow loop (maybe every 5 minutes) until $?=0
done

OR

I was also thinking can I just avoid all of this together and just check the exit status of the initial script? but I wasn't sure because if there was some sort of failure and the files weren't created then that would be a serious problem because the next part of the scanning process takes about 2 days...

Sorry if this might seem like a stupid question, I'm so deep in the google "if-until-exit-zero-else..." hole that I have no idea what to do from here.

Answer 1

To check that a named program or a script has finished, use the command:

wait $(pgrep program-name)