UNIX for Beginners Questions & Answers

@Don, but that may give unexpected results if the original field 9 contained wildcard characters, no?

Yes. But for the three filenames shown in post #5:
it works (assuming that the leading <double-quote> characters before "filename001_ABC " inside the ICODE tags was a typo).

Thank you so much for this tidbit. I modified what should be line number nine in the excerpt below which eliminated two lines of code that I came across elsewhere. Below is an excerpt of the shell script file that includes your code which seems to work as expected and hoped.
-

Code:

for a in $(ls *.*); do csplit -s -k -f "$a"_split $a /^ISA/ {*}; rm *split00; mv *split[0-9]* split/; mv $a original;done
cd split
for a in $(ls *split*); do sed ':a;N;$! ba;s/\n//g' < $a > "$a"_$(TZ=":US/Eastern" date -r $a +%Y%m%d_%H%M%SET); rm $a; done
for file in *split*
do
  if [ -r "$file" ]; then
#    IFS='~' read -a ${string[8]} < "$file"
    IFS='~' read x x x x x x x x string x < "$file"
    if [ "$string" ]; then
      mv -- "$file" "${file}_${string// }.edi"
     fi
  fi
done

Thank you again.

By the way, I wasn't able to get what you mentioned the following earlier but I imagine that I was implementing it incorrectly which resulted in the errors when I tried to tinker with it. If you don't mind, can you walk me through implementing the cleaner-looking method using the array, please?
-

What shell version do you use?
What "shebang" in the beginning of your script?
What did you do?
Which errors did you get?
What be the output of

Code:

IFS='~' read -a string <"$file"
echo ${string[8]}