Categorize files into sub-directories based on their file type.

sort_files.sh

#!/bin/bash

die () {
    echo -e "\033[0;31m$*\033[m" >&2
    exit 1
}

DIR=${1:-.}

if [ ! -d "$DIR" ]; then
    die "Not a valid dir!"
fi

for file in "$DIR"/* ; do
    if [ -f "$file" ]; then
        mime=$(file -ib "$file" | cut -f1 -d ';')
        if [ ! -d "$DIR/$mime" ]; then
            mkdir -p "$DIR/$mime" || die "Couldn't make the directory $mime. Check if it already exists!"
        fi
        mv "$file" "$DIR/$mime" || die "Moving the file $file to directory $mime failed!"
    elif [ -d "$file" ]; then
        echo "Skipping a directory $file"
    fi
done