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For detailed information on the individual functions, use the selection box on the right.

nni_get_interface

Syntax

int nni_get_interface( int iVersion, void** ppnni_func );

The function returns an instance of the Natural Native Interface.

An application calls this function after having retrieved and loaded the interface library with platform depending system calls. The function returns a pointer to a structure that contains function pointers to the individual interface functions. The functions returned in the structure may differ between interface versions.

Instead of a specific interface version, the caller can also specify the constant NNI_VERSION_CURR, which always refers to the most recent interface version. The interface version number belonging to a given Natural version is defined in the header file natni.h that is delivered with that version. In Natural Version n.n, the interface version number is defined as NNI_VERSION_nn. NNI_VERSION_CURR is also defined as NNI_VERSION_nn. If the Natural version against which the function is called does not support the requested interface version, the error code NNI_RC VERSION_ERROR is returned. Otherwise the return code is NNI_RC_OK.

The pointer returned by the function represents one instance of the interface. In order to use this interface instance, the application holds on to that pointer and passes it to subsequent interface calls.

Usually the application will subsequently initialize a Natural session by calling nni_initialize on the given instance. After the application has finished using that Natural session, it calls nni_uninitialize on that instance. After that it can initialize a different Natural session on the same interface instance. After the application has finished using the interface instance entirely, it calls nni_free_interface on that instance.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_free_interface

Syntax

int nni_free_interface(void* pnni_func);

An application calls this function after it has finished using the interface instance and has uninitialized the Natural session it hosts. The function frees the resources occupied by that interface instance.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_initialize

Syntax

int nni_initialize(void* pnni_func, const char* szCmdLine, void*, void*);

The function initializes a Natural session with a given command line. The syntax and semantics of the command line is the same as when Natural is started interactively. If a Natural session has already been initialized on the given interface instance, that session is implicitly uninitialized before the new session is initialized.

The command line must be specified in the way that the Natural initialization can be completed without user interaction. This means especially that if a program is passed on the stack or a startup program is specified, that program must not perform an INPUT statement that is not satisfied from the stack. Otherwise the subsequent behavior of the Natural session is undetermined.

The Natural session is initialized as batch session and in server mode. This means that the usage of certain statements and commands in the executed Natural modules is restricted.

When initalizing a Natural session under Natural Security, the command line must contain a LOGON command to a freely chosen default library under which the session will be started, and an appropriate user ID and password.

Example:

int iRes = 
pnni_func->nni_initialize( pnni_func, "STACK=(LOGON,MYLIB,MYUSER,MYPASS)", 0, 0);

If the application later calls nni_logon to a different library with a different user ID and afterwards calls nni_logoff, the Natural session will be reset to the library and user ID that was passed during nni_initialize.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_is_initialized

Syntax

int nni_is_initialized( void* pnni_func, int* piIsInit );

The function checks if the interface instance contains an initialized Natural session.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_uninitialize

Syntax

int nni_uninitialize(void* pnni_func);

The function uninitializes the Natural session hosted by the given interface instance.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_enter

Syntax

int nni_enter(void* pnni_func);

The function lets the current thread wait for exclusive access to the interface instance and the Natural session it hosts. A thread calls this function if it wants to issue a series of interface calls that may not be interrupted by other threads. The thread releases the eclusive access to the interface instance by calling nni_leave.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_try_enter

Syntax

int nni_try_enter(void* pnni_func);

The function behaves like nni_enter except that it does not block the thread and instead always returns immediately. If a different thread already has exclusive access to the interface instance, the function returns NNI_RC_LOCKED.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_leave

Syntax

int nni_leave(void* pnni_func);

The function releases exclusive access to the interface instance and allows other threads to access that instance and the Natural session it hosts.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_logon

Syntax

int nni_logon(void* pnni_func, const char* szLibrary, const char* szUser, const char* szPassword);

The function performs a LOGON to the specified Natural library.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_logoff

Syntax

int nni_logoff(void* pnni_func);

The function performs a LOGOFF from the current Natural library. This corresponds to a LOGON to the previously active library and user ID.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_callnat

Syntax

int nni_callnat(void* pnni_func, const char* szName, int iParm, struct parameter_description* rgDesc, struct natural_exception* pExcep);

The function calls a Natural subprogram.

The function receives its parameters as an array of parameter_description structures. The caller creates these structures using NNI functions in the following way:

• Use one the functions create_parm or create_module_parm to create an appropriate parameter set for the subprogram.

• If you have used create_parm, use the functions init_parm_* to initialize each parameter to the appropriate Natural data format. If you have used create_module_parm, the parameters are already initialized to the appropriate Natural data format.

• Assign a value to each parameter, using one the functions nni_put_parm or nni_put_parm_array.

• Call nni_get_parm on each parameter in the set. This fills the parameter_description structures.

• Pass the array of parameter_description structures to the function nni_callnat.

• After the call has been executed, extract the modified parameter values from the parameter set using the function nni_get_parm or nni_get_parm_array.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_create_object

Syntax

int nni_create_object(void* pnni_func, const char* szName, int iParm, struct parameter_description* rgDesc, struct natural_exception* pExcep); 

Creates a Natural object (an instance of a Natural class).

The function receives its parameters as a one-element array of parameter_description structures. The caller creates the structures using NNI functions in the following way:

• Use the function nni_create_parm to create parameter set with one element.

• Use the function nni_init_parm_s to initialize the parameter with the type HANDLE OF OBJECT.

• Call nni_get_parm_info on this parameter. This fills the parameter_description structure.

• Pass the parameter_description structure to the function nni_create_object.

• After the call has been executed, extract the modified parameter value from the parameter set using one the function nni_get_parm.

The parameters passed in rgDesc have the following meaning:

• The first (and only) parameter must be initialized with the data type HANDLE OF OBJECT and contains on return the Natural object handle of the newly created object.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_send_method

Syntax

int nni_send_method(void* pnni_func, const char* szName, int iParm, struct parameter_description* rgDesc, struct natural_exception* pExcep);

Sends a method call to a Natural object (an instance of a Natural class).

The function receives its parameters as an array of parameter_description structures. The caller creates these structures using NNI functions in the following way:

• Use the function nni_create_parm or nni_create_method_parm to create a matching parameter set.

• If you have used create_parm, use the functions init_parm_* to initialize each parameter to the appropriate Natural data format. If you have used nni_create_method_parm, the parameters are already initialized to the appropriate Natural data format.

• Assign a value to each parameter using one the functions nni_put_parm or nni_put_parm_array.

• Call nni_get_parm_info on each parameter in the set. This fills the parameter_description structures.

• Pass the array of parameter_description structures to the function nni_send_method.

• After the call has been executed, extract the modified parameter values from the parameter set using one of the nni_get_parm functions.

The parameters passed in rgDesc have the following meaning:

• The first parameter contains the object handle.

• The second parameter must be initialized to the data type of the method return value. If the method does not have a return value, the second parameter remains not initialized. On return from the method call, this parameter contains the return value of the method.

• The remaining parameters are the method parameters.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_get_property

Syntax

int nni_get_property(void* pnni_func, const char* szName, int iParm, struct parameter_description* rgDesc, struct natural_exception* pExcep); 

Retrieves a property value of a Natural object (an instance of a Natural class).

The function receives its parameters as an array of parameter_description structures. The caller creates these structures using NNI functions in the following way:

• Use the function nni_create_parm or nni_create_method_parm to create a matching parameter set.

• If you have used create_parm, use the functions init_parm_* to initialize each parameter to the appropriate Natural data format. If you have used create_method_parm, the parameters are already initialized to the appropriate Natural data format.

• Assign a value to each parameter using one the functions nni_put_parm or nni_put_parm_array.

• Call nni_get_parm_info on each parameter in the set. This fills the parameter_description structures.

• Pass the array of parameter_description structures to the function nni_send_method.

• After the call has been executed, extract the modified parameter values from the parameter set using one of the nni_get_parm functions.

The parameters passed in rgDesc have the following meaning:

• The first parameter contains the object handle.

• The second parameter is initialized to the data type of the property. On return from the property access, this parameter contains the property value.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_set_property

Syntax

int nni_set_property(void* pnni_func, const char* szName, int iParm, struct parameter_description* rgDesc, struct natural_exception* pExcep);

Assigns a property value to a Natural object (an instance of a Natural class).

The function receives its parameters as an array of parameter_description structures. The caller creates these structures using NNI functions in the following way:

• Use the function nni_create_parm or nni_create_prop_parm to create a matching parameter set.

• If you have used create_parm, use the functions init_parm_* to initialize each parameter to the appropriate Natural data format. If you have used create_prop_parm, the parameters are already initialized to the appropriate Natural data format. Assign a value to each parameter using one of the nni_put_parm functions.

• Assign a value to each parameter using one the functions nni_put_parm or nni_put_parm_array.

• Call nni_get_parm_info on each parameter in the set. This fills the parameter_description structures.

• Pass the array of parameter_description structures to the function nni_set_property.

The parameters passed in rgDesc have the following meaning:

• The first parameter contains the object handle.

• The second parameter contains the property value.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_delete_object

Syntax

int nni_delete_object(void* pnni_func, int iParm, struct parameter_description* rgDesc, struct natural_exception* pExcep);

Deletes a Natural object (an instance of a Natural class) created with nni_create_object.

The function receives its parameters as a one-element array of parameter_description structures. The caller creates the structures using NNI functions in the following way:

• Use the function nni_create_parm to create parameter set with one element.

• Use the function nni_init_parm_s to initialize the parameter with the type HANDLE OF OBJECT.

• Assign a value to the parameter using one the functions nni_put_parm.

• Call nni_get_parm_info on this parameter. This fills the parameter_description structure.

• Pass the parameter_description structure to the function nni_delete_object.

The parameters passed in rgDesc have the following meaning:

• The first (and only) parameter must be initialized with the data type HANDLE OF OBJECT and contains the Natural object handle of the object to be deleted.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_create_parm

Syntax

int nni_create_parm(void* pnni_func, int iParm, void** pparmhandle);

Creates a set of parameters that can be passed to a Natural module.

The parameters contained in the set are not yet initialized to specific Natural data types. Before using the parameter set in a call to nni_callnat, nni_create_object, nni_send_method, nni_set_property or nni_get_property:

• Initialize each parameter to the required Natural data type using one of the functions nni_init_parm_s, nni_init_parm_sa, nni_init_parm_d or nni_init_parm_da.

• Assign a value to each parameter using one of the functions nni_put_parm or nni_put_parm_array.

• Turn each parameter into a parm_description structure using the function nni_get_parm_info.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_create_module_parm

Syntax

int nni_create_module_parm(void* pnni_func, char chType, const char* szName, void** pparmhandle); 

Creates a set of parameters that can be used in a call to nni_callnat. The function enables an application to dynamically explore the signature of a callable Natural module.

The parameters contained in the returned set are already initialized to Natural data types according to the parameter data area of the specified module. Before using the parameter set in a call to nni_callnat:

• Assign a value to each parameter using one of the functions nni_put_parm or nni_put_parm_array.

• Turn each parameter into a parm_description structure using the function nni_get_parm_info.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_create_method_parm

Syntax

int nni_create_method_parm( void* pnni_func, const char* szClass, const char* szMethod, void** pparmhandle ); 

Creates a set of parameters that can be used in a call to nni_send_method. The function enables an application to dynamically explore the signature of a method of a Natural class.

The returned parameter set contains not only the method parameters, but also the other parameters required by nni_send_method. This means: If the method has n parameters, the parameter set contains n + 2 parameters.

• The first parameter in the set is initialized to the data type HANDLE OF OBJECT.

• The second parameter in the set is initialized to the data type of the method return value. If the method does not have a return value, the second parameter is not initialized.

• The remaining parameters in the set are initialized to the data types of the method parameters.

Before using the parameter set in a call to nni_send_method:

• Assign a value to each parameter using one of the functions nni_put_parm or nni_put_parm_array.

• Turn each parameter into a parm_description structure using the function nni_get_parm_info.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_create_prop_parm

Syntax

int nni_create_prop_parm(void* pnni_func, const char* szClass, const char* szProp,void** pparmhandle); 

Creates a set of parameters that can be used in a call to nni_get_property or nni_set_property. The returned parameter set contains all parameters required by nni_get_property or nni_set_property. The function enables an application to determine the data type of a property of a Natural class.

• The first parameter in the set is initialized to the data type HANDLE OF OBJECT.

• The second parameter in the set is initialized to the data type of the property.

Before using the parameter set in a call to nni_get_property or nni_set_property:

• Assign a value to each parameter using one of the functions nni_put_parm or nni_put_parm_array.

• Turn each parameter into a parm_description structure using the function nni_get_parm_info.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_parm_count

Syntax

int nni_parm_count( void* pnni_func, void* parmhandle, int* piParm )

The function retrieves the number of parameters in a parameter set.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_init_parm_s

Syntax

int nni_init_parm_s(void* pnni_func, int iParm, void* parmhandle, char chFormat, int iLength, int iPrecision, int iFlags); 

Initializes a parameter in a parameter set to a static data type.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_init_parm_sa

Syntax

int nni_init_parm_sa (void* pnni_func, int iParm, void* parmhandle, char chFormat, int iLength, int iPrecision, int iDim, int* rgiOcc, int iFlags); 

Initializes a parameter in a parameter set to an array of a static data type.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_init_parm_d

Syntax

int nni_init_parm_d(void* pnni_func, int iParm, void* parmhandle, char chFormat, int iFlags); 

Initializes a parameter in a parameter set to a dynamic data type.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_init_parm_da

Syntax

int nni_init_parm_da (void* pnni_func, int iParm, void* parmhandle, char chFormat, int iDim, int* rgiOcc, int iFlags); 

Initializes a parameter in a parameter set to an array of a dynamic data type.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_get_parm_info

Syntax

int nni_get_parm_info (void* pnni_func, int iParm, void* parmhandle, struct parameter_description* pDesc); 

Returns detailed information about a specific parameter in a parameter set.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_get_parm

Syntax

int nni_get_parm(void* pnni_func, int iParm, void* parmhandle, int iBufferLength, void* pBuffer); 

Returns the value of a specific parameter in a parameter set. The value is returned in the buffer at the address specified in pBuffer, with the size specified in iBufferLength. On successful return, the buffer contains the data in Natural internal format. See Natural Data Types on how to interpret the contents of the buffer.

If the length of the parameter according to the Natural data type is greater than iBufferLength, Natural truncates the data to the given length and returns the code NNI_RC_DATA_TRUNC. The caller can use the function nni_get_parm_info to request the length of the parameter value in advance.

If the length of the parameter according to the Natural data type is smaller than iBufferLength, Natural fills the buffer according to the length of the parameter and returns the length of the copied data in the return code.

If the parameter is an array, the function returns the whole array in the buffer. This makes sense only for fixed size arrays of fixed size elements, because in other cases the caller cannot interpret the contents of the buffer. In order to retrieve an individual occurrence of an arbitrary array use the function nni_get_parm_array.

If no memory of the size specified in iBufferLength is allocated at the adress specified in pBuffer, the results of the operation are unpredictable. Natural only checks that pBuffer is not null.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_get_parm_array

Syntax

int nni_get_parm_array(void* pnni_func, int parmnum, void* parmhandle, int iBufferLength, void* pBuffer, int* rgiInd);

Returns the value of a specific occurrence of a specific array parameter in a parameter set. The only difference to nni_get_parm is that array indices can be specified. The indices for unused dimensions must be specified as 0.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_get_parm_array_length

Syntax

int nni_get_parm_array_length(void* pnni_func, int iParm, void* parmhandle, int* piLength, int* rgiInd);

Returns the length of a specific occurrence of a specific array parameter in a parameter set.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_put_parm

Syntax

int nni_put_parm(void* pnni_func, int iParm, void* parmhandle, int iBufferLength, const void* pBuffer); 

Assigns a value to a specific parameter in a parameter set. The value is passed to the function in the buffer at the address specified in pBuffer, with the size specified in iBufferLength. See Natural Data Types on how to prepare the contents of the buffer.

If the length of the parameter according to the Natural data type is smaller than the given buffer length, the data will be truncated to the length of the parameter. The rest of the buffer will be ignored. If the length of the parameter according to the Natural data type is greater than the given buffer length, the data will copied only to the given buffer length, the rest of the parameter value stays unchanged. See Natural Data Types on the internal length of Natural data types.

If the parameter is a dynamic variable, it is automatically resized according to the given buffer length.

If the parameter is an array, the function expects the whole array in the buffer. This makes sense only for fixed size arrays of fixed size elements, because in other cases the caller cannot provide the correct contents of the buffer. In order to assign a value to an individual occurrence of an arbitrary array use the function nni_put_parm_array.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_put_parm_array

Syntax

int nni_put_parm_array(void* pnni_func, int iParm, void* parmhandle, int iBufferLength, const void* pBuffer, int* rgiInd);

Assigns a value to a specific occurrence of a specific array parameter in a parameter set. The only difference to nni_get_parm is that array indices can be specified. The indices for unused dimensions must be specified as 0.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_resize_parm_array

Syntax

int nni_resize_parm_array(void* pnni_func, int iParm, void* parmhandle, int* rgiOcc); 

Changes the occurrence count of a specific x-array parameter in a parameter set. For an n-dimensional array an occurrence count must be specified for all n dimensions. If the dimension of the array is less than 3, the value 0 must be specified for the not used dimensions.

The function tries to resize the occurrence count of each dimension either by changing the lower bound or the upper bound, whatever is appropriate for the given x-array.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_delete_parm

Syntax

int nni_delete_parm(void* pnni_func, void* parmhandle);

Deletes the specified parameter set.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_from_string

Syntax

int nni_from_string(void* pnni_func, const char* szString, char chFormat, int iLength, int iPrecision, int iBufferLength, void* pBuffer); 

Converts the string representation of a Natural P, N, D or T value into the internal representation of the value, as it is used in the functions nni_get_parm, nni_get_parm_array, nni_put_parm and nni_put_parm_array.

The string representations of these Natural data types look like this:

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

nni_to_string

Syntax

int nni_to_string(void* pnni_func, int iBufferLength, const void* pBuffer, char chFormat, int iLength, int iPrecision, int iStringLength, char* szString);

Converts the internal representation of a Natural P, N, D or T value, as it is used in the functions nni_get_parm, nni_get_parm_array, nni_put_parm and nni_put_parm_array, into a the string representation.

The string representations of these Natural data types look as described with the function nni_from_string.

Parameters

Return Codes

The meaning of the return codes is explained in the section Return Codes.

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