SAP FILE INTERFACE LOCKING

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ARTICLE

Locking Files
The file interface does not contain an integrated locking mechanism that ensures that only one ABAP program at a time can access a file. If multiple programs are writing to a file at the same time, the results are unpredictable.
To avoid this situation, use SAP locks or an unambiguous file name, such as UUIDs.

Note
When multiple application servers from the application layer try to access a file at the same time, conflicts can still occur despite SAP locks. This is the case, for example, when the operating system buffers data before writing it to a file.