Shell script read missing last line

Question

I have an ... odd issue with a bash shell script that I was hoping to get some insight on.

My team is working on a script that iterates through lines in a file and

Answer 1

Adding some additional info:

1. There's no need to use cat with while loop. while ...;do something;done<file is enough.
2. Don't read lines with for.

When using while loop to read lines:

1. Set the IFS properly (you may lose indentation otherwise).
2. You should almost always use the -r option with read.

with meeting the above requirements a proper while loop will look like this:

while IFS= read -r line; do
  ...
done <file

And to make it work with files without a newline at end (reposting my solution from here):

while IFS= read -r line || [ -n "$line" ]; do
  echo "$line"
done <file

Or using grep with while loop:

while IFS= read -r line; do
  echo "$line"
done < <(grep "" file)