Это определенно BAPI, потому что он находится в группе функций, названной бизнес-объектом BUS1001006
Стандартный материал
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But I agree with Sandra this definition is very blurry as it was created long-long ago and is used hither and yon.
Use this module with version specification of when the BAPI was created. Depending on version the output varies.
CALL FUNCTION 'BAPI_MONITOR_GETLIST'
EXPORTING
SHOW_RELEASE = '620'
TABLES
BAPILIST = api
.
Where to get version? Of course, by finding the module in BAPI transaction in the BUS1001006 section
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Moreover, for your total confusion there are two different BAPIs almost identical in names: BAPI_MATERIAL_GETALL and BAPI_MATERIAL_GET_ALL, one older and one yonger, and the first marked as a wrapper for the latter.
It is a usual situation when SAP decided to revamp the API and left old stuff for legacy.
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Так что да, все сложно. Это всегда с SAP.