$UserBaseDirectory gives the base directory in which user-specific files to be loaded by Mathematica are conventionally placed.
CUDAQ[] returns True if a CUDA-capable device is available and False otherwise.
MakeJavaExpr[expr] constructs a new Java object of the J/Link Expr class that represents the Mathematica expression expr.
MLINK getMathLink (WolframLibraryData libData) gets a MathLink connection to use for evaluations in Mathematica.
mcomplex*MTensor_getComplexData (MTensor t) gets an array of the data elements of an MTensor of complex type.
mint*MTensor_getIntegerData (MTensor t) gets an array of the data elements of an MTensor of integer type.
double*MTensor_getRealData (MTensor t) gets an array of the data elements of an MTensor of real type.
TetGenCreate[] creates an instance of a TetGen expression.
TetGenExpression[id] represents an instance of a TetGen object.
TetGenExpressions[] returns a list of active TetGen expressions.