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Return storage container size of registered data type


extern size_t ssGetDataTypeStorageContainerSize
                                          (SimStruct *S, DTypeId



SimStruct representing an S-function block.


Data type ID of the registered data type for which you want to know the container size.


This function returns the storage container size of the data type designated by dataTypeId. This function returns the same value as would the sizeof( ) function; it does not return the word length of either the storage container or the data type. To get the word length of the storage container, use ssGetDataTypeFxpContainWordLen. To get the word length of the data type, use ssGetDataTypeFxpWordLength.

The container of the size returned by this function stores input and output signals, run-time parameters, and DWorks during Simulink® simulations. It is also the appropriate size measurement to pass to functions like memcpy( ).

This function errors out when ssGetDataTypeIsFxpFltApiCompat returns FALSE.


To use this function, you must include fixedpoint.h and fixedpoint.c. For more information, see Structure of the S-Function.




An sfix24_En10 data type has a word length of 24, but is actually stored in 32 bits during simulation. For this signal,

  • ssGetDataTypeStorageContainerSize or sizeof( ) returns 4, which is the storage container size in bytes.

  • ssGetDataTypeFxpContainWordLen returns 32, which is the storage container word length in bits.

  • ssGetDataTypeFxpWordLength returns 24, which is the data type word length in bits.

TLC Functions


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