How to write a script to prompt for filename to search and print all files on that filename

Question

I have to write a script that prompts the user to enter a filename and then prints all the files on the system with that file name. So far I have this on my script.sh:

#!/bin/bash
echo "please enter filename"
read filename

if [ find . -name $filename ] //not sure if the condition is right
then
    //print all files on the system with that file name 
    not sure what to put here
else
    echo "file does not exist"
fi

Please help, thanks!

Answer 1

You can use something like:

#!/bin/bash
echo "please enter filename"
read filename

find . -name "$filename" | egrep '.*'

if [ "$?" -ne 0 ] 
then
    echo "file does not exist"
fi

Answer 2

For the simple task of finding all files that has a certain name using bash, you don't need find. The find utility is more use useful for instances where you actually need to do operations on the found files.

The bash shell has a special ** pattern that matches "recursively" down into subdirectories. This pattern is enabled by setting the globstar shell option.

#!/bin/bash

shopt -s globstar dotglob nullglob

pathnames=( ./**/"$1" )

if [[ ${#pathnames[@]} -gt 0 ]]; then
    printf 'Found "%s"\n' "${pathnames[@]}"
else
    printf 'Found no file named "%s"\n' "$1"
fi

This would expand the pattern ./**/"$1", which matches all the filenames corresponding to the script's first command line argument anywhere in the current directory or below it. The resulting pathnames are stored in the array pathnames. A test is then carried out on the length of this array, and if it contains something (the array has a length greater than zero), the elements of the array are printed out. If the array is empty, a message to this effect is printed.

The shell options dotglob and nullglob makes sure that shell globbing patterns matches hidden files and that the pattern is completely removed if it doesn't match anything, respectively.

Note that the script (like your attempted code) does not make any distinction between regular files, directories, symbolic links or other types of files.

Testing this script:

$ bash ~/script.sh .zshrc
Found "./.zsh/.zshrc"
Found "./skel/.zshrc"

$ cd /etc
$ bash ~/script.sh .zshrc
Found no file named ".zshrc"

Without this script, setting the failglob and globstar shell options in bash would allow us to do effectively the same thing as the script directly on the command line:

$ shopt -s globstar failglob dotglob

$ echo ./**/.zsh
./.zsh

$ echo ./**/.zshrc
./.zsh/.zshrc ./skel/.zshrc

$ echo ./**/booo
bash: no match: ./**/booo