Cheat Sheet #day49

`touch` Command Cheatsheet

The touch command in Unix/Linux is used primarily to create empty files or update the access and modification times of existing files. Below are the basic and advanced usages of the touch command along with practical examples.

Basic Usage

Create an empty file
```
  touch filename
```
Create multiple empty files
```
  touch file1 file2 file3
```
Update the timestamp of an existing file
```
  touch filename
```

Common Options

Change only the access time
```
  touch -a filename
```
Change only the modification time
```
  touch -m filename
```

Use a specific date and time

  touch -t [[CC]YY]MMDDhhmm[.ss] filename

Reference another file's timestamps
```
  touch -r reference_file filename
```
Do not create files (only change timestamps)
```
  touch -c filename
```

Examples

Create a single empty file
```
  touch file.txt
```
Create multiple empty files
```
  touch file1.txt file2.txt file3.txt
```
Update the timestamp of an existing file
```
  touch existing_file.txt
```
Change only the access time
```
  touch -a file.txt
```
Change only the modification time
```
  touch -m file.txt
```
Set a specific date and time
```
  touch -t 202406302359.59 file.txt
```

Reference another file's timestamps

  touch -r reference_file.txt target_file.txt

Do not create files if they do not exist
```
  touch -c file.txt
```

Advanced Usage

Create a file with a specific timestamp
```
  touch -t 202406302359.59 file.txt
```
Use the current time as the timestamp
```
  touch -d "now" file.txt
```

Set the timestamp to a specific date using -d

  touch -d "2023-06-30 23:59:59" file.txt

Practical Tips

Creating Empty Files: Use touch to quickly create placeholder files or to create files required by scripts or applications.
Updating Timestamps: Use touch to update the access or modification times of files without modifying their contents.
Setting Specific Timestamps: Use the -t or -d options to set specific timestamps, which can be useful for testing or when working with log files.

Quick Reference

Create an empty file:
```
  touch filename
```
Update access time:
```
  touch -a filename
```
Update modification time:
```
  touch -m filename
```

Set specific date and time:

  touch -t [[CC]YY]MMDDhhmm[.ss] filename

Reference another file's timestamps:
```
  touch -r reference_file filename
```
Do not create files:
```
  touch -c filename
```

This cheatsheet covers the essential commands and options for using touch effectively, from creating empty files to updating and setting specific timestamps. Adjust the commands according to your specific requirements and environment.

Cheat Sheet #day49 - touch

touch Command Cheatsheet