B3270

b3270 is a generic back end for 3270 emulators. b3270 implements the 3270 protocol and host input/output, and communicates with a front end application (the thing that actually draws the image of the terminal display on the screen and captures keystrokes) using a simple XML- or JSON-based protocol. It is currently used by wx3270.



How do I configure and run it?
b3270 can be invoked interactively for basic experimentation. It does not have a prompt, and produces its responses and indications asynchronously. Obviously, this is not the usual way to run it. Normally it is started as a child of some other process, with actions written to its standard input and responses captured from its standard output. It can also be configured to accept actions via HTTP requests.

b3270 uses resource definitions for its configuration, which can be set in a number of different ways:
 * Specifying a session file (a file with resource definitions in xrdb format) on the b3270 command line. A b3270 session file has the suffix .b3270.
 * Specifying individual command-line options when you invoke b3270. These override definitions from a session file.

b3270 also allows a number of options to be changed at run-time via the Set action, but these changes are not saved -- you need to use one of the above methods to make your changes apply to the next session.