Program-to-Program Communications
About the PPC Toolbox
This topic describes how you can use the Program-to-Program
Communications (PPC) Toolbox to send and receive low-level message blocks
between applications.
The PPC Toolbox can be used by different applications located on the same
computer or across a network of Macintosh computers. The PPC Toolbox is
available only in System 7.0.or above. To test for the existence of the
PPC Toolbox, use the Gestalt function.
Read this topic if you want your application to transmit and receive data from
other applications that support the PPC Toolbox.
Applications that utilize the PPC Toolbox must be open and connected to each
other to exchange data. The PPC Toolbox allows you to send large amounts of
data to other applications; it is typically useful for code that is not
event-based. The PPC Toolbox is called by the Macintosh Operating System
and can also be called by applications, device drivers, desk accessories, or
other programs.
The PPC Toolbox provides a method of communication that is particularly
useful for applications that are specifically designed to work together and are
dependent on each other for information. For example, suppose one user
organizes large amounts of data using a database application and another user
filters and plots the same data using a plotting application. If both applications
use the PPC Toolbox, these two applications can directly transmit data to
each other when both applications are open and connected to each other.
You can also use the PPC Toolbox if your application communicates with
other applications using high-level events or Apple events, and your
application allows the user to choose another application to communicate with.
You can use a PPC Toolbox routine that provides a standard user interface to
display a dialog box on the user's screen that lists other applications that are
available to exchange information.
The PPC Toolbox uses the AppleTalk Data Stream Protocol (ADSP) and the
Name-Binding Protocol (NBP). For detailed information on ADSP or NBP, see
the AppleTalk Manager description.
Note: The sample applications "store data," "display data," "send and
receive," "make memo," and "spell quick" used in this discussion are not actual
Apple products. They are used for illustrative purposes only.
The PPC Toolbox provides you with the ability to
exchange data with other open applications on the same computer or
across a network of Macintosh computers
browse through a listing of applications that are available to exchange
data
verify user identities for communication across a network
To utilize the PPC Toolbox to exchange data between open applications, each
application involved must support the PPC Toolbox.
The PPC Toolbox topics detail how to
set up your application for communication
use security features prior to establishing communication
locate other applications that can exchange data
initiate communication between applications
accept or reject incoming communications requests
transmit and receive data between applications
terminate communication between applications