script

#!/bin/bash

path=$1         # 1st arg is the path to be searched
regex=$2        # 2nd arg is a regular expression
searchTerm=$3       # 3rd arg is an optional search term
startDir=`pwd`      # Stores the starting path

getDirs() {     # Function to get the directories


    for i in "$1"/*; do         # for the entire contents of the dir passed
        if [ -d "$i" ]; then        # if a directory is found
            echo "$i" >> temp.txt   # add it to temp
            getDirs "$i"        # repeat the process for each dir found
        fi
    done
}

getFiles() {        # Function to get files matching the regex

    for a in $directories; do
        cd "$a"
        temp=`ls -1 | grep $regex`

        for j in $temp; do
            echo "$a/"$j""
        done
    done
}

searchFiles() {         # Function to search within files


    for a in $output1; do
        out=`grep -n "$searchTerm" $a | cut -d: -f 1`   # Using colon as delimiter to remove the line returned by grep
        for i in $out; do
            echo "$a: line $i"
        done
    done
}

numArgs=$#

echo "$path" >> temp.txt            # Adding original path as the getDirs function will not find it
getDirs $path                   # Getting directories to search

directories=`cat temp.txt`

output1=`getFiles`

cd $startDir

if [ $numArgs == 3 ]; then  # If a search term was specified by the user
    searchFiles     # Then look for that search term in the files found
else
    echo "$output1"
fi

rm temp.txt                     # Removing temporary files
exit 0