Linux cp Command: Complete File and Directory Copy Guide

The cp (copy) command is used to copy files and directories in Linux. This guide covers everything from basic copying to advanced operations with attribute preservation.

Basic Syntax

cp [options] source destination

Common Options

• -r, -R: Recursively copy directories
• -p: Preserve mode, ownership, timestamps
• -a: Archive mode (same as -dR —preserve=all)
• -i: Interactive mode (prompt before overwrite)
• -u: Update mode (copy only when source is newer)
• -v: Verbose mode (explain what’s being done)
• -l: Create hard links instead of copying
• -s: Create symbolic links instead of copying

Real-World Examples

1. Basic File Copying

# Copy single file
$ cp source.txt destination.txt

# Copy multiple files
$ cp file1.txt file2.txt directory/

# Copy with specific name
$ cp original.txt backup_original.txt

2. Directory Copying

# Copy directory recursively
$ cp -r source_dir/ destination_dir/

# Copy directory contents
$ cp -r source_dir/* destination_dir/

# Copy with full preservation
$ cp -a /source/dir/ /dest/dir/

3. Advanced Copying

# Copy only newer files
$ cp -u *.txt backup/

# Copy with progress
$ cp -v large_file.iso /media/backup/

# Create backup with timestamp
$ cp file.txt file.txt.$(date +%Y%m%d)

Common Use Cases

1. Backup Operations

   # Backup configuration
   cp -a /etc/nginx/nginx.conf{,.backup}
   
   # Backup with date
   cp -a config.ini config.ini.$(date +%Y%m%d)
   

2. Project Management

   # Copy project template
   cp -r template/ new_project/
   
   # Copy specific file types
   cp -r src/*.{js,css} dist/
   

3. System Administration

   # Copy with permissions
   sudo cp -p /etc/passwd{,.bak}
   
   # Copy system files
   sudo cp -a /var/lib/mysql/* /backup/mysql/
   

Tips and Tricks

1. Preserve Attributes

   # Copy with all attributes
   cp -av source_dir/ dest_dir/
   
   # Copy with specific attributes
   cp --preserve=mode,ownership file1 file2
   

2. Safe Copying

   # Interactive mode
   cp -i important.txt backup/
   
   # No clobber (don't overwrite)
   cp -n source.txt destination.txt
   

3. Efficient Copying

   # Update only
   cp -ru source_dir/ backup_dir/
   
   # Copy with hard links
   cp -al source_dir/ snapshot_dir/
   

Best Practices

1. Use Appropriate Options

   # For configuration files
   sudo cp -a /etc/config.conf{,.bak}
   
   # For user data
   cp -rp ~/documents/* ~/backup/
   

2. Verify Copies

   # Use verbose mode
   cp -v file.txt backup/
   
   # Check with diff
   diff -r source_dir/ dest_dir/
   

3. Handle Special Files

   # Copy device files
   cp -a /dev/sda1 /dev/backup_sda1
   
   # Copy sparse files
   cp --sparse=always large_file backup/
   

Common Errors and Solutions

1. Permission Denied

   # Solution: Use sudo
   sudo cp restricted.txt /etc/
   

2. No Space Left

   # Check space first
   df -h
   # Use compression
   tar czf - source_dir | (cd /dest && tar xzf -)
   

3. File Exists

   # Solution: Use -i or -n
   cp -i source.txt destination.txt
   

Related Commands

• mv: Move/rename files
• rsync: Advanced file copying
• dd: Copy and convert files
• tar: Archive files

Advanced Usage

1. Copying with Pattern Matching

# Copy multiple file types
cp -r src/*.{html,css,js} dist/

# Exclude patterns
cp -r source_dir/ dest_dir/ --exclude="*.tmp"

2. Backup Strategies

#!/bin/bash
# Incremental backup script
backup_dir="/backup/$(date +%Y-%m-%d)"
cp -al /backup/latest "$backup_dir"
cp -au /source/* "$backup_dir/"
ln -nsf "$backup_dir" /backup/latest

3. Network Copying

# Using cp with ssh
tar cf - source_dir | ssh user@remote "cd /dest && tar xf -"

# Using rsync (alternative)
rsync -av source_dir/ user@remote:/dest/dir/

Special Use Cases

1. Large File Copying

# Copy with progress
pv source.iso | cp /dev/stdin destination.iso

# Resume interrupted copy
rsync --partial --progress source.iso dest/

2. Directory Structure Only

# Copy directory structure without files
cp -R --attributes-only source_dir/ dest_dir/

3. Sparse File Handling

# Efficiently copy sparse files
cp --sparse=always large_sparse_file backup/

Remember that cp is a fundamental command for file management in Linux. Understanding its options and best practices helps ensure safe and efficient file operations while maintaining file attributes and permissions as needed.