Check if a file exists inside a "Variable" Path

Question

I am trying to find if a file exist in an iPhone application directory

Unfortunately, apps directory differs from a device to another

On my device, i use the following command to see if the file exists:

if  [[ -f "/var/mobile/Applications/D0D2B991-3CDA-457B-9187-1F02A84FF3AB/AppName.app/filename.txt" ]]; then 
    echo "The File Exists"; 
else
    echo "The File Does Not Exist";
fi 

I want a command that would automatically search if the file exist without the need to specify the "variable" name inside the path.

I tried this:

if  [[ -f "/var/mobile/Applications/*/AppName.app/filename.txt" ]]; then 
    echo "The File Exists"; 
else 
    echo "The File Does Not Exist"; 
fi 

But no luck, it didn't find the file,

Maybe because i have 2 path of /var/mobile/Applications/*/AppName.app/ since i have cloned the app.

I would like to get a way to be able to find if the file filename.txt exists inside any folder named AppName.app inside this directory /var/mobile/Applications/*/

Answer 1

You can do this as follows:

[[ $(find /var/mobile/Applications/*/AppName.app/ -name filename.txt -print -quit | wc -l) -gt 0 ]] && echo "The File Exists" || echo "The File Does Not Exist"

Answer 2

The -f test can only take one argument. You would need to put it in a loop to check if some glob exists and its matches some regular file, i.e.

shopt -s nullglob
found=
for file in /var/mobile/Applications/*/AppName.app/filename.txt; do
  [[ -f $file ]] && found=: && break
done
[[ -n $found ]] && echo "The File Exists" || echo "The File Does Not Exist"

If you're not sure specifically where the file is located you can use find, doing something like below which will exit early if found. (should work for gnu find, haven't tested on bsd)

if [[ -f $(find /some_root_directory -type f -name 'filename.txt' -print -quit) ]]; then
    echo "The File Exists"
else
    echo "The File Does Not Exist"
fi

Answer 3

# if a glob matches nothing, remove it instead of leaving the literal glob
shopt -s nullglob 

# stick all matches in an array
files=( /var/mobile/Applications/*/AppName.app/filename.txt )

case "${#files[@]}" in
  0 ) echo "Sorry, no such file." ;;
  1 ) echo "The file exists: ${files[0]}" ;;
  * ) echo "There are multiple files matching this pattern: ${files[*]}" ;;
esac

Answer 4

I like this technique for the purpose:

if find /var/mobile/Applications/*/AppName.app/ -name filename.txt -print -quit | grep -q .; then
    echo "The File Exists"
else
    echo "The File Does Not Exist"
fi

This has some advantages over this form:

[[ $(find ..... -print -quit | wc -l) -gt 0 ]]

Because:

• It doesn't need a $() subshell
• It doesn't need to count lines with wc
• It doesn't need to compare numbers with the -gt operator
• It doesn't need to be inside a [[ ... ]]

Basically it's a find ... | grep -q . versus [[ $(find ... | wc -l) -gt 0 ]]

Or find ... | grep -q . versus [[ -f $(find ...) ]]