bash script for putting thousands of files, into separate folders - bash

Question

in a directory, i have thousands of files.
i use the following bash snippet, in order to make these thousands of files, be put in folders, that have each 1000 files,
and i face two issues:
a) now each folder has a prefix of dir_ while i would like it to have a name, that will have 6 digits, if less than 6 in the folder name, leading zeros should be added appropriately.
b) current script, puts first folder, into the last one, for example, i have dir_400325 as the last folder, and in there,i find the bash script i have run, and the dir_1000 folder, which is the first folder created. How could i change this, so the first folder, is not stored into the last one?
#!/bin/bash
c=0; d=1000; mkdir -p dir_${d}
for file in *
do
if [ $c -eq 1000 ]
then
d=$(( d + 1000 )); c=0; mkdir -p dir_${d}
fi
mv "$file" dir_${d}/
c=$(( c + 1 ))
done

Answer 1

You can use printf and a format string to generate your 6-digit directory name with leading zeros (%06d), demonstrated in a shell:
bash-4.4$ d=1001
bash-4.4$ dir_name=$(printf "/path/to/%06d" $d)
bash-4.4$ echo $dir_name
/path/to/001001
Using an absolute path may help ensure the files end up where you're expecting them and not in some subfolder of your current working directory.
#!/bin/bash
c=0
d=1000
dir_name=$(printf "/path/to/%06d" $d)
mkdir -p $dir_name
for file in *
do
if [ $c -eq 1000 ]
then
c=0
d=$(( d + 1000 ))
dir_name=$(printf "/path/to/%06d" $d)
mkdir -p $dir_name
fi
if [[ -f "$file" ]]
then
mv "$file" $dir_name
c=$(( c + 1 ))
fi
done