How to Get File Creation and Modification Dates/Times in Shell/Bash

 When working with files in a shell or bash environment, it’s often useful to retrieve metadata such as file creation and modification dates/times. Below are several methods to achieve this across different platforms like Linux and Windows.

1. Modification Date/Time

Retrieving the modification date and time of a file is straightforward and works across both Linux and Windows platforms.

# Using the `stat` command
stat -c %y filename.txt

• Output: This command returns the last modification time of the file filename.txt.

2. Creation Date/Time

Getting the file creation date/time is platform-dependent:

On Linux:

• Linux filesystems generally do not store the creation date (crtime) in an easily accessible way. The stat command typically only returns the last modification time, access time, and status change time.

However, for filesystems that do store creation time (like ext4), you can use the following command (requires root access and debugfs):

# Using debugfs (works for ext4)
sudo debugfs -R 'stat <filename.txt>' /dev/sda1 | grep 'crtime'

• Output: The command returns the creation time (crtime) of the file.

On Windows:

• Windows does store the creation time, which can be accessed via the following command:

# Using the `stat` command with PowerShell
(Get-Item filename.txt).CreationTime

• Output: This returns the creation time of filename.txt.

3. Cross-Platform Python Solution

If you need a cross-platform solution that works on both Linux and Windows, consider using a Python script. Python provides methods to retrieve both modification and creation times.

import os
import platform

def get_file_times(path_to_file):
    # Get modification time
    mod_time = os.path.getmtime(path_to_file)
    creation_time = None

    # Get creation time based on OS
    if platform.system() == 'Windows':
        creation_time = os.path.getctime(path_to_file)
    else:
        stat = os.stat(path_to_file)
        try:
            creation_time = stat.st_birthtime
        except AttributeError:
            # Linux doesn't support creation time natively
            creation_time = mod_time
    
    return (creation_time, mod_time)

# Example usage
path = "filename.txt"
creation_time, mod_time = get_file_times(path)
print(f"Creation Time: {creation_time}")
print(f"Modification Time: {mod_time}")

• Output: This Python script returns both the creation and modification times of the file, with fallback logic for platforms that don’t support creation time natively (e.g., Linux).

While obtaining the modification time is consistent across platforms, the creation time is not as straightforward, particularly on Linux. If cross-platform compatibility is essential, using a Python script as shown above is a reliable approach. On Linux, for most practical purposes, the modification time might suffice when creation time isn’t available.