getScalarBoolean Read scalar boolean data from a gateway argument.

## Syntax

    int getScalarBoolean(void* _pvCtx, int* _piAddress, int* _piBool)

    int getNamedScalarBoolean(void* _pvCtx, const char* _pstName, int* _piBool)

## Arguments

_pvCtx

  Scilab environment pointer, pass in "pvApiCtx" provided by api_scilab.h.

_piAddress

  Address of the Scilab variable.

_pstName

  Name of the variable for "named" functions.

_piBool

  Return boolean value.

## Return value

if successful 0, otherwise print error(s) message(s) in the Scilab console and returns first error number.