låsfil

A låsfil, or lock file, is a mechanism used in computing to prevent simultaneous access to a shared resource. This is crucial for maintaining data integrity and preventing conflicts when multiple processes or users might try to modify the same file or data structure at the same time. When a process needs to access a shared resource, it first attempts to create or acquire a lock file. If the lock file already exists, it indicates that another process is currently using the resource, and the requesting process must wait. Once the resource is no longer needed, the process that was using it removes or releases the lock file, allowing other processes to access it.

The implementation of lock files can vary. A simple approach is to create an empty file with a specific name. The presence of this file signals that the resource is locked. More sophisticated systems might use dedicated locking mechanisms provided by the operating system or database. The naming convention for lock files is important for identifying the resource they protect. For example, a file named "data.txt.lock" might indicate that the "data.txt" file is currently in use. Proper handling of lock files is essential; failing to release a lock can lead to deadlocks, where processes indefinitely wait for each other.