Application Programming Interfaces (API) can be used to do data transfer between SAP and external system.
1. Initializing APIs – FM: CALO_INIT_API must be called firstly if need to call APIs for classes, variants, BOMs and ECM.
And the parameters are defined defaul values.
2. APIs for the log – FM: CALO_DB_LOG_ON_OFF is used switch on/off the log processes.
And FM: CALO_MSG_APPEND_DB_LOG is used for writing log
FM: CALO_LOG_READ_MESSAGES is used for reading log