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## Preprocessor Constants and Basic Typedefs

The C header file `lt_base.h` should be included by all source files using the MrSID SDK. It includes four other C headers (`lt_define.h`, `lt_platform.h`, `lt_status.h`, and `lt_types.h`), which contain definitions for the following:

- miscellaneous preprocessor constants and macros used throughout the SDK
- preprocessor constants that define the compiler, OS, etc. used by the current target environment
- the `LT_STATUS` type used throughout the SDK for success/failure return values, and some common status codes
- the typedefs used by the SDK for the primitive/integral datatypes