Python: How to Safely Create Directories (Check Before Creation)

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Okay, here’s a comprehensive article on safely creating directories in Python, with a focus on checking before creation, fulfilling the length requirement, and incorporating best practices:

Python: How to Safely Create Directories (Check Before Creation)

Introduction

Creating directories (folders) is a fundamental operation in many software applications. Whether you’re building a data processing pipeline, a web application that handles user uploads, or a simple script to organize files, the ability to programmatically create directories is essential. Python provides straightforward methods for directory creation, but relying solely on these basic methods without proper checks can lead to errors, race conditions, and potential security vulnerabilities.

This article delves deep into the nuances of safely creating directories in Python. We’ll cover not only the basic os.mkdir() and os.makedirs() functions but also explore robust techniques to verify directory existence, handle potential errors gracefully, and avoid common pitfalls. We’ll examine different scenarios, including creating single directories, nested directory structures, and dealing with concurrent access. The emphasis throughout will be on checking before creation to ensure the reliability and safety of your code.

1. The Basics: os.mkdir() and os.makedirs()

Python’s os module provides the core functionality for interacting with the operating system, including directory manipulation. The two primary functions for directory creation are:

  • os.mkdir(path, mode=0o777): This function creates a single directory at the specified path.

    • path: A string representing the path to the new directory. This can be a relative path (relative to the current working directory) or an absolute path.
    • mode: (Optional) An integer representing the permissions to set on the new directory. The default is 0o777 (octal representation), which grants read, write, and execute permissions to the owner, group, and others. It’s crucial to understand and use appropriate permissions for security. We’ll discuss permissions in detail later.
    • Raises FileExistsError: If a directory with the same name already exists at the specified path.
    • Raises FileNotFoundError: If any of the parent directories in the path do not exist.

  • os.makedirs(path, mode=0o777, exist_ok=False): This function creates a directory and, if necessary, all the intermediate directories in the path. It’s like a recursive version of os.mkdir().

    • path: The path to the new directory (and any necessary parent directories).
    • mode: (Optional) The permissions for the created directories.
    • exist_ok: (Optional, Python 3.2+) A boolean flag.
      • If False (default), a FileExistsError is raised if the target directory already exists.
      • If True, no error is raised if the target directory already exists. However, it will still raise an error if intermediate directories cannot be created due to permissions or other issues.
    • Raises FileExistsError: If exist_ok=False and the target directory already exists.
    • Raises OSError: For other errors, such as permission issues or if a file (not a directory) exists at a path component intended to be a directory.

Simple Examples:

“`python
import os

Create a single directory

try:
os.mkdir(“my_new_directory”)
print(“Directory ‘my_new_directory’ created successfully.”)
except FileExistsError:
print(“Directory ‘my_new_directory’ already exists.”)
except FileNotFoundError:
print(“Parent directory does not exist.”)
except OSError as e:
print(f”An error occurred: {e}”)

Create a nested directory structure

try:
os.makedirs(“parent_dir/child_dir/grandchild_dir”)
print(“Nested directories created successfully.”)
except FileExistsError:
print(“Target directory already exists.”)
except OSError as e:
print(f”An error occurred: {e}”)

Create a directory, ignoring if it already exists (Python 3.2+)

os.makedirs(“another_directory”, exist_ok=True)
print(“Directory ‘another_directory’ created (or already existed).”)
“`

2. The Importance of Checking Before Creation

The examples above show basic usage, but they highlight a critical point: blindly calling os.mkdir() or os.makedirs() without checking if the directory already exists can lead to errors. This is especially important in:

  • Multi-threaded or multi-process environments: If multiple threads or processes attempt to create the same directory simultaneously, a race condition can occur. One process might check for the directory’s existence, find it doesn’t exist, and then get interrupted. Another process might create the directory in the meantime. When the first process resumes, it will try to create the directory again, resulting in a FileExistsError.
  • Long-running scripts: If a script runs for an extended period, the file system state might change between the time the script checks for a directory and the time it attempts to create it.
  • User input: If the directory path is based on user input, you cannot assume the user won’t provide a path that already exists.
  • Data consistency: In some cases, the existence of a directory might be a signal that a certain operation has already been performed. Trying to create it again might indicate a logic error or lead to data corruption.

Therefore, always checking for the directory’s existence before attempting to create it is a crucial best practice.

3. Methods for Checking Directory Existence

Python offers several ways to determine if a directory exists:

  • os.path.exists(path): This function returns True if the given path (file or directory) exists, and False otherwise. This is the most general check, as it works for both files and directories.

  • os.path.isdir(path): This function returns True if the given path exists and is a directory. It returns False if the path doesn’t exist or if it refers to a file. This is the preferred method for specifically checking for directory existence.

  • pathlib.Path.exists() and pathlib.Path.is_dir() (Python 3.4+): The pathlib module provides an object-oriented way to interact with files and directories. The Path object has methods that are equivalent to the os.path functions.

Examples:

“`python
import os
import pathlib

Using os.path.exists()

if os.path.exists(“my_directory”):
print(“The path ‘my_directory’ exists.”)
else:
print(“The path ‘my_directory’ does not exist.”)

Using os.path.isdir()

if os.path.isdir(“my_directory”):
print(“‘my_directory’ is a directory.”)
else:
print(“‘my_directory’ is not a directory (or does not exist).”)

Using pathlib (Python 3.4+)

my_path = pathlib.Path(“my_directory”)
if my_path.exists():
print(“The path ‘my_directory’ exists (pathlib).”)
else:
print(“The path ‘my_directory’ does not exist (pathlib).”)

if my_path.is_dir():
print(“‘my_directory’ is a directory (pathlib).”)
else:
print(“‘my_directory’ is not a directory (or does not exist) (pathlib).”)
“`

4. Combining Checks and Creation: Best Practices

Now, let’s put it all together. Here are robust patterns for creating directories, incorporating existence checks and error handling:

4.1. Basic Pattern (Single Directory):

“`python
import os

def create_directory_safe(path):
“””
Creates a single directory if it doesn’t already exist.

Args:
    path: The path to the directory.

Returns:
    True if the directory was created, False if it already existed.
    Raises OSError for other errors.
"""
if not os.path.isdir(path):
    try:
        os.mkdir(path)
        print(f"Directory '{path}' created successfully.")
        return True
    except OSError as e:
        print(f"Error creating directory '{path}': {e}")
        raise  # Re-raise the exception to be handled by the caller
else:
    print(f"Directory '{path}' already exists.")
    return False

Example usage:

create_directory_safe(“my_new_dir”)
create_directory_safe(“my_new_dir”) # Will print “already exists”
“`

4.2. Pattern with makedirs() and exist_ok (Nested Directories):

“`python
import os

def create_nested_directory_safe(path):
“””
Creates a directory and its parent directories if they don’t exist.

Args:
    path: The path to the directory.

Returns:
    None.  Raises OSError for errors other than the directory already existing.
"""
try:
    os.makedirs(path, exist_ok=True)
    print(f"Directory '{path}' created (or already existed).")
except OSError as e:
    print(f"Error creating directory '{path}': {e}")
    raise

Example usage:

create_nested_directory_safe(“parent/child/grandchild”)
create_nested_directory_safe(“parent/child/grandchild”) # No error, already exists
“`

4.3. Pattern with pathlib (More Object-Oriented):

“`python
import pathlib

def create_directory_pathlib(path_str):
“””
Creates a directory (and parent directories) using pathlib.

Args:
    path_str: The path to the directory (as a string).

Returns:
    A pathlib.Path object representing the created directory.
    Raises OSError for errors.
"""
path = pathlib.Path(path_str)
try:
    path.mkdir(parents=True, exist_ok=True)
    print(f"Directory '{path}' created (or already existed) (pathlib).")
    return path
except OSError as e:
    print(f"Error creating directory '{path}': {e}")
    raise

Example usage:

dir_path = create_directory_pathlib(“pathlib_example/subdir”)
print(f”Created directory: {dir_path.resolve()}”) # Get the absolute path
“`

4.4. Handling Race Conditions with Retries (Advanced):

Even with the checks above, race conditions are theoretically possible, although much less likely. If you absolutely need to guarantee directory creation in a highly concurrent environment, you can implement a retry mechanism:

“`python
import os
import time
import random

def create_directory_with_retries(path, max_retries=5, retry_delay=0.1):
“””
Creates a directory with retries to handle potential race conditions.

Args:
    path: The path to the directory.
    max_retries: The maximum number of retries.
    retry_delay: The base delay between retries (in seconds).

Returns:
    True if the directory was created, False otherwise.
"""
for attempt in range(max_retries):
    if not os.path.isdir(path):
        try:
            os.mkdir(path)
            print(f"Directory '{path}' created successfully (attempt {attempt + 1}).")
            return True
        except FileExistsError:
            # Another process might have created it in the meantime.
            print(f"Directory '{path}' already exists (attempt {attempt + 1}).  Retrying...")
            time.sleep(retry_delay + random.uniform(0, 0.1))  # Add some jitter
        except OSError as e:
            print(f"Error creating directory '{path}' (attempt {attempt + 1}): {e}")
            return False  # Don't retry for other errors
    else:
        print(f"Directory '{path}' already exists.")
        return True  # Directory exists, consider it a success

print(f"Failed to create directory '{path}' after {max_retries} attempts.")
return False

Example Usage

if create_directory_with_retries(“retry_dir”):
print(“Directory creation successful (with retries).”)
else:
print(“Directory creation failed (with retries).”)
“`

This code attempts to create the directory. If a FileExistsError occurs, it waits for a short, randomized delay and tries again. This helps to avoid situations where multiple processes are constantly colliding. The random.uniform(0, 0.1) adds “jitter” to the delay, making it slightly different for each process, further reducing the chance of repeated collisions. The max_retries parameter prevents the function from looping indefinitely.

5. Directory Permissions (Understanding mode)

The mode parameter in os.mkdir() and os.makedirs() controls the permissions of the created directory. Permissions determine who can access and modify the directory and its contents. Understanding permissions is critical for security.

Permissions are typically represented in octal notation (base-8). Each digit in the octal number represents a set of permissions:

  • First digit (leftmost): Special permissions (setuid, setgid, sticky bit – rarely used for directories in typical applications). We’ll usually set this to 0.
  • Second digit: Permissions for the owner of the directory.
  • Third digit: Permissions for the group associated with the directory.
  • Fourth digit: Permissions for others (everyone else).

Each of these three digits (owner, group, others) is a combination of the following bits:

  • 4 (Read): Allows listing the contents of the directory.
  • 2 (Write): Allows creating, deleting, and renaming files within the directory. Note: Write permission on a directory does not automatically grant write permission to files inside the directory. File permissions are separate.
  • 1 (Execute): Allows “entering” the directory (i.e., using it as part of a path). Without execute permission, you cannot access files within the directory, even if you have read permission.

Common Permission Values:

  • 0o777 (rwxrwxrwx): Full permissions for everyone (owner, group, others). Generally not recommended for security reasons unless specifically needed.
  • 0o755 (rwxr-xr-x): Full permissions for the owner, read and execute for group and others. This is a common and reasonably secure default. It allows the owner full control, while others can list and access files within the directory.
  • 0o700 (rwx——): Full permissions for the owner, no permissions for group and others. This is the most restrictive setting, suitable for directories containing sensitive data.
  • 0o644 (-rw-r–r–): Common for files. Read and write for the owner, read-only for group and others.

Example (Setting Permissions):

“`python
import os
import stat # For symbolic permission constants

Create a directory with owner-only permissions

try:
os.mkdir(“sensitive_data”, mode=0o700)
print(“Directory ‘sensitive_data’ created with owner-only permissions.”)
except OSError as e:
print(f”Error: {e}”)

Create a directory with specific permissions using stat constants

try:
os.mkdir(“shared_data”, mode=(stat.S_IRUSR | stat.S_IWUSR | stat.S_IXUSR | # Owner: rwx
stat.S_IRGRP | stat.S_IXGRP | # Group: r-x
stat.S_IROTH | stat.S_IXOTH)) # Others: r-x
print(“Directory ‘shared_data’ created with specific permissions.”)
except OSError as e:
print(f”Error: {e}”)

Using pathlib to set permission

import pathlib

dir_path = pathlib.Path(“pathlib_permissions”)
try:
dir_path.mkdir(mode=0o750) #Owner rwx, group rx, others no permission.
print(f”‘{dir_path}’ created with permission 750″)
except OSError as e:
print(f”Error: {e}”)
“`

The stat module provides symbolic constants (e.g., stat.S_IRUSR for “read permission for owner”) that make it easier to specify permissions without memorizing the octal values. This is generally preferred for readability.

Important Considerations for Permissions:

  • Security: Always use the least permissive settings that are necessary for your application. Avoid 0o777 unless absolutely required.
  • User and Group: The owner and group of a directory are determined by the user and group that execute the Python script.
  • umask: The umask (user mask) is a system-level setting that masks (removes) certain permissions when files and directories are created. For example, if the umask is 0o022, the write permission for group and others will be removed, regardless of the mode specified in os.mkdir(). You can get the current umask using os.umask(0) (this also temporarily sets it to 0 and returns the previous value; you should restore it afterward). You generally don’t need to modify the umask within your Python script unless you have a very specific reason to do so.
  • Inheritance (ACLs): On some file systems (e.g., those supporting Access Control Lists – ACLs), directories can inherit permissions from their parent directories. This is a more advanced topic beyond the scope of this basic guide.
  • Changing Permissions: If you need to change permissions after a directory is created, use os.chmod(path, mode) (or pathlib.Path.chmod(mode)).

6. Temporary Directories

Sometimes, you need to create a directory that is only used temporarily, and you want it to be automatically deleted when it’s no longer needed. Python’s tempfile module provides functions for creating temporary files and directories.

“`python
import tempfile
import os

Create a temporary directory

with tempfile.TemporaryDirectory() as temp_dir:
print(f”Temporary directory created: {temp_dir}”)

# Use the temporary directory...
file_path = os.path.join(temp_dir, "my_temp_file.txt")
with open(file_path, "w") as f:
    f.write("This is a temporary file.")

# ...

The temporary directory (and its contents) is automatically deleted

when the ‘with’ block exits.

print(“Temporary directory deleted.”)

You can also specify a prefix, suffix and parent directory

with tempfile.TemporaryDirectory(suffix=”suffix”, prefix=”prefix“, dir=os.getcwd()) as tmpdir:
print(f”Temporary directory with prefix, suffix and directory: {tmpdir}”)
“`

The tempfile.TemporaryDirectory() context manager is the recommended way to create temporary directories. The directory is created when the with block is entered, and it’s automatically deleted (along with all its contents) when the with block exits, even if exceptions occur. This ensures proper cleanup and avoids leaving temporary files and directories scattered around the system.

You can also use tempfile.mkdtemp() to create a temporary directory without using a context manager. However, you are then responsible for deleting the directory yourself, which is more error-prone. The with statement approach is highly preferred.

7. Error Handling and Exceptions

As demonstrated in the examples throughout this article, robust error handling is essential when working with directories. Here’s a summary of the key exceptions and how to handle them:

  • FileExistsError: Raised by os.mkdir() or os.makedirs(exist_ok=False) if the target directory already exists. You should almost always check for this condition before calling these functions, but it’s still good practice to have a try...except block to catch it, especially in concurrent environments.
  • FileNotFoundError: Raised by os.mkdir() if any of the parent directories in the path do not exist. os.makedirs() handles this automatically by creating the necessary parent directories.
  • OSError: A more general exception that can be raised for various reasons, including:
    • Permission errors (PermissionError is a subclass of OSError): You don’t have the necessary permissions to create the directory.
    • Disk full: There is no space left on the device.
    • Invalid path: The path contains invalid characters or is too long.
    • File exists at a component of the path: A file (not a directory) exists where you’re trying to create a directory.

Best Practices for Error Handling:

  • Use try...except blocks: Wrap your directory creation code in try...except blocks to catch potential exceptions.
  • Be specific: Catch the most specific exceptions first (e.g., FileExistsError before OSError).
  • Handle errors gracefully: Don’t just let the program crash. Log the error, inform the user (if appropriate), and take appropriate action (e.g., retry, exit the program, or use a different directory).
  • Re-raise exceptions: If your function cannot handle an error itself, re-raise the exception using raise so that the calling code can handle it. This allows for proper error propagation.
  • Consider logging: Use Python’s logging module to record errors and other important events. This can be invaluable for debugging.

8. Path Manipulation and Validation

Before creating a directory, it’s often necessary to manipulate or validate the path. Here are some useful techniques:

  • os.path.join(path, *paths): Safely joins one or more path components, handling separators correctly for the operating system. Always use this instead of manually concatenating path strings.

  • os.path.abspath(path): Returns the absolute (normalized) version of a path.

  • os.path.relpath(path, start=os.curdir): Returns a relative path to path from the start directory (defaults to the current working directory).

  • os.path.basename(path): Returns the final component of a path (the file or directory name).

  • os.path.dirname(path): Returns the directory part of a path.

  • pathlib equivalents: The pathlib module provides object-oriented methods for all of these operations (e.g., Path.joinpath(), Path.resolve(), Path.relative_to(), Path.name, Path.parent).

  • Path Validation (Custom): You might need to perform custom validation on a path, such as:

    • Checking for invalid characters.
    • Ensuring the path is within a specific allowed range.
    • Limiting the path length.

    You can use regular expressions or custom functions for these checks.

Example (Path Manipulation):

“`python
import os
import pathlib

os.path methods

base_dir = “/home/user/data”
sub_dir = “images”
file_name = “picture.jpg”

full_path_os = os.path.join(base_dir, sub_dir, file_name)
print(f”Full path (os.path): {full_path_os}”)

absolute_path_os = os.path.abspath(“my_relative_dir”)
print(f”Absolute path (os.path): {absolute_path_os}”)

pathlib methods

base_path = pathlib.Path(“/home/user/data”)
sub_path = pathlib.Path(“images”)
file_path = pathlib.Path(“picture.jpg”)

full_path_pathlib = base_path / sub_path / file_path # Using the / operator
print(f”Full path (pathlib): {full_path_pathlib}”)

absolute_path_pathlib = pathlib.Path(“my_relative_dir”).resolve()
print(f”Absolute path (pathlib): {absolute_path_pathlib}”)

Example of simple custom path validation

def validate_path(path_str):
invalid_chars = [“<“, “>”, “:”, ‘”‘, “/”, “\”, “|”, “?”, “*”] # Example invalid characters
for char in invalid_chars:
if char in path_str:
return False
return True
test_path = “my/valid/path”
test_invalid_path = “my/invalid<path”

if validate_path(test_path):
print(f”‘{test_path}’ is a valid path”)
else:
print(f”‘{test_path}’ is an invalid path”)

if validate_path(test_invalid_path):
print(f”‘{test_invalid_path}’ is a valid path”)
else:
print(f”‘{test_invalid_path}’ is an invalid path”)

“`

9. Working with Symbolic Links (Symlinks)

Symbolic links (symlinks) are special files that point to other files or directories. When working with directories, it’s important to be aware of how symlinks are handled.

  • os.path.isdir() and os.path.exists() follow symlinks: If you call os.path.isdir() on a symlink that points to a directory, it will return True. Similarly, os.path.exists() will return True if the symlink points to an existing file or directory.

  • os.path.islink(path): Returns True if path is a symbolic link (regardless of whether the target exists).

  • os.makedirs() and symlinks: os.makedirs() will not create intermediate directories if they are symlinks pointing to non-existent targets. It will only create actual directories.

  • pathlib.Path.is_symlink(): Returns True if the path is a symbolic link

  • os.symlink(src, dst): Creates a symbolic link named dst that points to src. Be careful with symlinks, as they can introduce security risks if not handled properly.

“`python
import os
import pathlib

Create a directory and a symlink to it

if not os.path.isdir(“original_dir”):
os.mkdir(“original_dir”)
print(“Created ‘original_dir'”)
if not os.path.exists(“symlink_to_dir”):
os.symlink(“original_dir”, “symlink_to_dir”)
print(“Created ‘symlink_to_dir'”)

Check if it’s a directory (follows symlink)

print(f”‘symlink_to_dir’ is a directory: {os.path.isdir(‘symlink_to_dir’)}”)

Check if it’s a symlink

print(f”‘symlink_to_dir’ is a symlink: {os.path.islink(‘symlink_to_dir’)}”)

Using pathlib

orig_dir = pathlib.Path(“original_pathlib_dir”)
symlink_dir = pathlib.Path(“symlink_pathlib_dir”)

if not orig_dir.exists():
orig_dir.mkdir()
if not symlink_dir.exists():
symlink_dir.symlink_to(orig_dir)

print(f”‘{symlink_dir}’ is a directory(pathlib): {symlink_dir.is_dir()}”)
print(f”‘{symlink_dir}’ is a symlink(pathlib): {symlink_dir.is_symlink()}”)

Clean up (optional – but good practice, especially with symlinks!)

if os.path.islink(“symlink_to_dir”):
os.remove(“symlink_to_dir”)
print(“Removed symlink ‘symlink_to_dir'”)
if os.path.isdir(“original_dir”):
os.rmdir(“original_dir”) # Only works if the directory is empty
print(“Removed ‘original_dir'”)
if symlink_dir.is_symlink():
symlink_dir.unlink() #removes the symlink
if orig_dir.exists():
orig_dir.rmdir()
“`

10. Atomic Operations (Advanced)

In highly concurrent scenarios, even the retry mechanism described earlier might not be sufficient to guarantee that a directory is created only once. Ideally, we would want an atomic operation – an operation that is guaranteed to either complete entirely or not at all, with no intermediate states.

Unfortunately, standard Python doesn’t provide a truly atomic directory creation function across all operating systems. However, there are some platform-specific techniques and external libraries that can provide atomic or near-atomic behavior:

  • os.link() and os.rename() (POSIX systems): On POSIX-compliant systems (like Linux and macOS), you can use a combination of os.link() and os.rename() to achieve a near-atomic directory creation. The idea is:

    1. Create a temporary directory with a unique name.
    2. Create a hard link to the temporary directory using os.link(). Hard links are essentially multiple names for the same underlying data on the file system.
    3. Rename the hard link to the desired final directory name using os.rename(). os.rename() is atomic on POSIX systems if the source and destination are on the same file system.
      This approach relies that if multiple processes attempt these operations, hard-link creation fails if file exists, preventing duplicates.

    “`python
    import os
    import tempfile
    import uuid

    def atomic_create_directory(path):
    “””
    Atomically creates a directory on POSIX systems.

    Args:
    path: The desired directory path.

Returns:
    True if the directory was created, False if it already exists.
    Raises OSError for other errors.
"""
if os.path.isdir(path):
    return False  # Already exists

temp_dir = tempfile.mkdtemp()  # Create a temporary directory
try:
    temp_link = os.path.join(temp_dir, str(uuid.uuid4()))  # Unique name for the hard link

    # Create hard link
    try:
        os.link(temp_dir, temp_link)
    except OSError as e:
        if e.errno == 17: # File Exists Error - meaning another process won.
            return False #directory already exists.
        else:
            raise

    # Atomically rename the hard link to the final name
    try:
        os.rename(temp_link, path)
    except OSError as e:
        if e.errno == 17: # File exists
            return False # Another process beat us to it
        else:
            raise

    print(f"Directory '{path}' created atomically.")
    return True
finally:
    # Clean up the temporary directory (and the hard link, if it exists)
    try:
        if os.path.exists(temp_link):
            os.remove(temp_link)
        os.rmdir(temp_dir)  # rmdir only works on empty directories
    except OSError:
        pass  # Ignore errors during cleanup - we tried our best

    Example usage

    if atomic_create_directory(“atomic_dir”):
    print(“Atomic directory creation succeeded”)
    else:
    print(“Atomic directory already existed”)

    “`

  • Windows: Windows doesn’t have a direct equivalent of os.link() for directories. The CreateDirectory() Win32 API function can be used with specific flags to achieve near-atomic behavior, but this requires using the ctypes module to interact directly with the Windows API, which is significantly more complex.

  • External Libraries: Libraries like filelock can provide cross-platform locking mechanisms that can be used to synchronize directory creation across multiple processes or threads. This is often a simpler and more portable solution than trying to implement atomic operations yourself.

11. Using the filelock Library

The filelock library provides a simple way to implement file-based locks, which can be used to serialize directory creation across multiple processes or threads.

“`python
import os
from filelock import FileLock

def create_directory_with_lock(path):
“””Creates a directory using a file lock for synchronization.”””
lock_path = path + “.lock” # Create a lock file associated with the directory
lock = FileLock(lock_path)

with lock:  # Acquire the lock
    if not os.path.isdir(path):
        try:
            os.makedirs(path, exist_ok=True)
            print(f"Directory '{path}' created (with lock).")
            return True
        except OSError as e:
            print(f"Error creating directory '{path}': {e}")
            raise
    else:
        print(f"Directory '{path}' already exists (with lock).")
        return False

Example usage

if create_directory_with_lock(“locked_dir”):
print(“Locked creation successful”)
else:
print(“Directory already exists (locked creation)”)
``
TheFileLockobject acquires a lock on the specified file (lock_path). Thewith lock:` statement ensures that the lock is automatically released when the block exits, even if exceptions occur. Only one process or thread can hold the lock at a time, preventing race conditions.

12. Best Practices Checklist

Here’s a summary of the key best practices for safely creating directories in Python:

  1. Always Check Before Creating: Use os.path.isdir() or pathlib.Path.is_dir() to verify if the directory already exists before attempting to create it.
  2. Use os.makedirs(exist_ok=True): For creating nested directories, use os.makedirs() with the exist_ok=True flag to avoid errors if the target directory already exists.
  3. Handle Exceptions: Wrap your directory creation code in try...except blocks to catch FileExistsError, FileNotFoundError, and OSError.
  4. Use Appropriate Permissions: Set the mode parameter correctly to ensure the desired level of access control. Avoid 0o777 unless absolutely necessary. Start with more restrictive permissions (e.g., 0o755 or 0o700) and loosen them only if required.
  5. Use pathlib (Optional): Consider using the pathlib module for a more object-oriented approach to path manipulation.
  6. Use os.path.join(): Always use os.path.join() (or pathlib.Path.joinpath() or / operator with pathlib) to construct paths, instead of manual string concatenation.
  7. Consider Temporary Directories: For temporary directories, use tempfile.TemporaryDirectory() to ensure automatic cleanup.
  8. Handle Race Conditions: In highly concurrent environments, use a retry mechanism or consider atomic operations (using os.link() and `os

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