Rename multiple files sequentially and starting by the same prefix

I have a folder containing like 1500 files, I want to rename them automatically via the terminal or a shell script as follows: "prefix_number.extension".
Example: cin_1.jpg, cin_2.png ...

Try:

count=0; for f in *; do [ -f "$f" ] && mv -i "$f" "cin_$((++count)).${f##*.}"; done

Or, if you prefer your commands spread over multiple lines:

count=0
for f in *
do
    [ -f "$f" ] && mv -i "$f" "cin_$((++count)).${f##*.}"
done

How it works

• count=0

  This initializes the variable count to zero.

• for f in *; do

  This starts a loop over all files in the current directory.

• [ -f "$f" ] && mv -i "$f" "cin_$((++count)).${f##*.}"

  [ -f "$f" ] tests to see if the file $f is a regular file (not a directory).

  If $f is a regular file, then the move (mv) command is run. -i tells mv not to overwrite any existing files without asking. "cin_$((++count)).${f##*.}" is the name of the new file. cin_ is the prefix. $((++count)) returns the value of count after it has been incremented. ${f##*.} is the extension of file $f.

• done

  This marks the end of the loop.

Example

Consider a directory with these three files:

$ ls
alpha.jpg  beta.png  gamma.txt

Let's run our command:

$ count=0; for f in *; do [ -f "$f" ] && mv -i "$f" "cin_$((++count)).${f##*.}"; done

After running our command, the files in the directory now are:

$ ls
cin_1.jpg  cin_2.png  cin_3.txt

A rename oneliner:

rename -n 's/.+\./our $i; sprintf("cin_%d.", 1+$i++)/e' *

This matches every file with a dot in its name (the last one, if multiple) and renames the part until the dot with cin_ followed by an incrementing number and a dot. With the -n flag it just prints what it would do, remove it to perform the renaming.

Example run

$ ls
a.jpg  b.jpg  d.png  e.png
$ rename -n 's/.+\./our $i; sprintf("cin_%d.", 1+$i++)/e' *
rename(a.jpg, cin_1.jpg)
rename(b.jpg, cin_2.jpg)
rename(d.png, cin_3.png)
rename(e.png, cin_4.png)
$ rename 's/.+\./our $i; sprintf("cin_%d.", 1+$i++)/e' *
$ ls
cin_1.jpg  cin_2.jpg  cin_3.png  cin_4.png

Source: How to rename multiple files sequentially from command line?