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Figure 1-1. How APIs Fit into the AS/400 Business Computing System Structure
Using APIs—Benefits
Although some CL commands and some OS/400 APIs perform the same basic
functions, APIs often can provide additional performance improvements and access
to functions. Benefits for using APIs include the following:
APIs are slightly faster than the following:
– Using the equivalent command or calling a CL program to call the
command.
– Coding a call to a command by using the Process Commands (QCAPCMD)
API because the API is saved the overhead of processing a command.
When you call an API, you do not have to go through the command ana-
lyzer.
– Using the system function in the ILE C language that processes com-
mands.
1-2 System API Programming V4R1