The four GridRPC call functions may be categorized by a combination of two properties: block- ing behavior and calling sequence. A call may be either blocking (synchronous) or non-blocking (asynchronous) and it may use either a variable number of arguments (like printf) or anargument stack calling sequence. The argument stack calling sequence allows building the list of arguments to the function at runtime through elementary stack operations, such as push and pop.
grpc_call makes a blocking remote procedure call with a variable number of arguments.
grpc_call_async makes a non-blocking remote procedure call with a variable number of arguments.
grpc_call_argstack makes a blocking call using the argument stack.
grpc_call_argstack_async makes a non-blocking call using the argument stack.