Sometimes you may want to create temporary file or directories for the life of the process and then you want them deleted once the process terminates or the file is closed. This is very useful to store some metadata or temporary data but you don’t want the data to persist in the filesystem. We can achieve that by creating temporary file which is available in almost all languages such as Python and C. The way temporary file works is as follows:
- Creates a file with random name
- Make the file mode “wb+” which means create it for reading/writing and truncate if it exists
- Unlink the file right after creation. This will guarantee that the file will be deleted after the process terminates
- Return the file object to the caller
Once we close the file or all the process(es) that has a reference to the file terminates, the file will be removed. The same thing applies to temporary directories.
Example in Python:
import tempfile
# Create temp file
fp = tempfile.TemporaryFile()
# Write to the file
fp.write("First write!")
# Read from the beginning
fp.seek(0)
fp.read() #=> "First write!"
# Now the file will be closed and removed
fp.close()