tempfile Module¶

The tempfile module creates temporary files and directories with automatic cleanup. It is essential for safe temporary storage without polluting the file system.

Named Temporary Files¶

Creating Temp Files¶

import tempfile
import os

with tempfile.NamedTemporaryFile(mode='w', delete=False) as f:
    f.write("Temporary content")
    temp_name = f.name

print(f"File: {temp_name}")
print(f"Exists: {os.path.exists(temp_name)}")

os.unlink(temp_name)

Output:

File: /tmp/tmpXXXXXXXX
Exists: True

Auto-Cleanup Context Manager¶

import tempfile

with tempfile.NamedTemporaryFile(mode='w', delete=True) as f:
    f.write("Data")
    f.flush()
    print(f"Writing to {f.name}")

print(f"After context: file deleted")

Output:

Writing to /tmp/tmpXXXXXXXX
After context: file deleted

Temporary Directories¶

Creating Temp Directories¶

import tempfile
import os

with tempfile.TemporaryDirectory() as tmpdir:
    filepath = os.path.join(tmpdir, "file.txt")
    with open(filepath, 'w') as f:
        f.write("Data")
    print(f"Created: {filepath}")

print(f"Directory cleaned up")

Output:

Created: /tmp/tmpXXXXXXXX/file.txt
Directory cleaned up

SpooledTemporaryFile¶

In-Memory Until Size Limit¶

import tempfile

with tempfile.SpooledTemporaryFile(max_size=1024, mode='w+') as f:
    f.write("Small data")
    f.seek(0)
    print(f.read())

Output:

Small data

Practical Usage¶

Temporary Processing¶

import tempfile
import os

data = ["line1\n", "line2\n", "line3\n"]

with tempfile.NamedTemporaryFile(mode='w', suffix='.txt', delete=False) as f:
    f.writelines(data)
    temp_file = f.name

with open(temp_file, 'r') as f:
    lines = f.readlines()
    print(f"Read {len(lines)} lines")

os.unlink(temp_file)

Output:

Read 3 lines