FileDeleteTest::testInUse in modules/simpletest/tests/file.test
Tries deleting a file that is in use.
FilePrivateTestCase::testPrivateFile in modules/file/tests/file.test
Tests file access for file uploaded to a private node.
FileUsageTest::testGetUsage in modules/simpletest/tests/file.test
Tests file_usage_list().
file_delete in includes/file.inc
Deletes a file and its database record.
file_field_delete_file in modules/file/file.field.inc
Decrements the usage count for a file and attempts to delete it.
file_managed_file_validate in modules/file/file.module
An #element_validate callback for the managed_file element.
system_cron in modules/system/system.module
Implements hook_cron().