Bash Script - Find Largest File

#bash #linux

find_largest_file.sh

Find the single largest file in $HOME with human-readable output.

Usage

Make executable:

chmod +x find_largest_file.sh

Run:

./find_largest_file.sh

Example Output

Searching for the largest file in /home/ben...

Largest file found:
Path : /home/ben/media/Skyfall.mp4

Size : 2,147,483,648 bytes (2 GB)

Details

Recursively searches $HOME (includes all subdirectories like Documents, Downloads, etc.)
Byte counts include comma separators via sed
Units auto-scale (KB/MB/GB/TB) via bc
Gracefully handles permission errors
Avoids polluting system $PATH variable

Requirements
Standard Unix tools: find, sort, cut, sed, bc

#!/bin/bash
# Find the largest file in the user's home directory

SEARCH_DIR="$HOME"

echo "Searching for the largest file in $SEARCH_DIR..."

# Find largest file
result=$(find "$SEARCH_DIR" -type f -printf '%s\t%p\n' 2>/dev/null | sort -n | tail -n 1)

if [[ -z "$result" ]]; then
    echo "No files found or permission denied in $SEARCH_DIR"
    exit 1
fi

# Split size and path
SIZE=$(echo "$result" | cut -f1)
FILE_PATH=$(echo "$result" | cut -f2-)  # Changed from PATH to FILE_PATH

# Function for human-readable size (using bc for portability)
human_size() {
    local size=$1
    local value=$size
    local unit="B"

    if [ $size -ge 1099511627776 ]; then
        value=$(echo "scale=1; $size / 1099511627776" | bc)
        unit="TB"
    elif [ $size -ge 1073741824 ]; then
        value=$(echo "scale=1; $size / 1073741824" | bc)
        unit="GB"
    elif [ $size -ge 1048576 ]; then
        value=$(echo "scale=1; $size / 1048576" | bc)
        unit="MB"
    elif [ $size -ge 1024 ]; then
        value=$(echo "scale=1; $size / 1024" | bc)
        unit="KB"
    fi

    # Remove trailing .0 if present
    value=${value%\.0}

    echo "$value $unit"
}

HUMAN_SIZE=$(human_size "$SIZE")

# Format raw bytes with commas for readability using sed
SIZE_FMT=$(echo "$SIZE" | sed ':a;s/\B[0-9]\{3\}\>/,&/;ta')

echo "-------------------------------------"
echo "Largest file found:"
echo "Path : $FILE_PATH"
echo "Size : $SIZE_FMT bytes ($HUMAN_SIZE)"
echo "-------------------------------------"

exit 0