What happens if one process reads data from a file while another process tries to delete it?

If one process reads data from a file, and another tries to delete it, the behavior depends on the operating system and file system.

In Unix-like systems, the file will not be immediately deleted if it is open by another process. Deleting the file removes its link from the directory, but the file itself remains on disk until all processes close their descriptors. Thus, the reading process can continue working, and the file will be physically deleted later.

In Windows, attempting to delete a file that is open by another process usually results in an error — the file cannot be deleted while it is in use.

Therefore:

• In Unix: reading continues, deletion is deferred.
• In Windows: deletion will not occur until the file is closed.

For safe file handling in a multi-process environment, it is recommended to use locking mechanisms or access synchronization.