Linux Shell Scripting: Script Check - linux

Question

I am new to Linux bash scripting and I can't seem to find what I'm doing wrong. Here's my code. Entering number 2 and 3, after the prompt that I ask the user my code stops it doesn't continue to the IF ELSE statements. Thank you to those who will help!
#!/bin/bash
while true
do
clear
echo "Please enter one of the following options"
echo "1. Move empty files"
echo "2. Check file size"
echo "3. Which file is newer"
echo "4. File check rwx"
echo "5. Exit".
echo -e "Enter Choice:"
read answer
case "$answer" in
1) ./move_empty
exit 55 ;;
2) echo "Enter a filename"
read filename
if [ -f $filename ];
then ./file_size
fi
;;
3) echo "Enter first file:"
read filename
echo "Enter second file:"
read filename2
if [ ! -f "$filename" ];
then
echo "Supplied file name" $filename "does not exist";
if [ $filename" -nt $filename" ]; then
echo $filename "is newer"
exit 1fi
fi ;;
5) exit ;;
esac
done

Answer 1

If you have completed the check at ShellCheck.net, then you should have received:
$ shellcheck myscript
No issues detected!
If you didn't work it down to that point, you are not done. You have multiple quoting problems in your script and you compare $filename -nt $filename (which is always false). Small "attention to detail" issues that make a big difference. ShellCheck.net does a thorough job, but will not find logic issues, those are left to you. The cleanup of your quoting would look similar to:
#!/bin/bash
while true
do
clear
echo "Please enter one of the following options"
echo "1. Move empty files"
echo "2. Check file size"
echo "3. Which file is newer"
echo "4. File check rwx"
echo "5. Exit".
echo -n "Enter Choice: "
read -r answer
case "$answer" in
1) ./move_empty
exit 55
;;
2) echo -n "Enter a filename: "
read -r filename
if [ -f "$filename" ]
then
./file_size
fi
;;
3) echo -n "Enter first file: "
read -r filename
echo -n "Enter second file: "
read -r filename2
if [ ! -f "$filename2" ]
then
echo "Supplied file name $filename does not exist";
if [ "$filename" -nt "$filename2" ]; then
echo "$filename is newer"
exit 1
fi
fi
;;
5) exit
;;
esac
done
(note: you do not need echo -e as there are no backslash escaped characters to handle in your prompt, likely you intended -n to prevent the addition of a newline at the end of the prompt)
(also note: the use of clear, while fine for some terminals, will cause problems with others. Just be aware of the potential issue.)
If your then is on the same line with your conditional expression, e.g. if [ "$filename" -nt "$filename2" ]; then then a ';' is needed after the closing ']' to indicate a newline, otherwise, there is no need for a ';'.
Logic Problems
As discussed, the logic problems are not caught by ShellCheck and you must work though the code. It looks like you intended something like the following:
3) echo -n "Enter first file: "
read -r filename
echo -n "Enter second file: "
read -r filename2
if [ ! -f "$filename" ] || [ ! -f "$filename2" ]
then
echo "Supplied file '$filename' or '$filename2' does not exist";
exit 1
fi
if [ "$filename" -nt "$filename2" ]; then
echo "$filename is newer"
else
echo "$filename2 is newer"
fi
;;
You just have to take it line by line...
Look things over and let me know if you have further questions.