Class to be used by Working with OMERO and server components to allow a uniform creation of temporary files and folders with a best-effort guarantee of deleting the resources on exit. The manager searches three locations in order, taking the first which allows lockable write-access (See #1653):

  • The environment property setting OMERO_TMPDIR
  • The user’s home directory, for example specified in Java via System.getProperty("user.home")
  • The system temp directory, in Java System.getProperty("java.io.tmpdir") and in Python tempfile.gettempdir()

Creating temporary files

For the user “ralph”,

from omero.util.temp_files import create_path
path = create_path("omero",".tmp")


import omero.util.TempFileManager
File file = TempFileManager.create_path("omero",".tmp")

both produce a file under the directory:


where $PID is the current process id and $RANDOM is some random sequence of alphanumeric characters.

Removing files

If remove_path is called on the return value of create_path, then the temporary resources will be cleaned up immediately. Otherwise, when the Java or Python process exits, they will be deleted. This is achieved in Java through Runtime#addShutdownHook(Thread) and in Python via atexit.register().

Creating directories

If an entire directory with a unique directory is needed, pass “true” as the “folder” argument of the create_path method:

create_path("omero", ".tmp", folder = True)


TempFileManager.create_path("omero", ".tmp", true);


All contents of the generated directory will be deleted.

See also