Generate unique filename for fswebcam

Question

I have fswebcam installed in my ubuntu. I want the fswebcam to provide output as img1, img2 (if img1 is there), img3, img4... etc

I tried:

sudo fswebcam img

It stores the files as img but replaces the existing one instead of storing as img2.
Is there any specific type of unix command to store the filename as I specified?

Answer 1

location="your location directory"
cd $location
ls
fname='filename'
i=1
j=1
    sudo fswebcam $fname 
    if [ -f $fname ]
    then
        echo "exist"
        while [ -f $fname$i ]
        do
            echo $fname$i
            i=$((i + j))
        done
        mv $fname $fname$i
    else
        echo "oops not found"
    fi