Chapter4.Operating and Debugging in Direct Mode

Chapter4.Operating and Debugging in Direct Mode

Table of Contents

Operating in Direct Mode

Entering Direct Mode

Functionality Available in Direct Mode

Exiting Direct Mode

Debugging a Routine in Direct Mode

Creating and Displaying M Routines

Executing M Routines Interactively

Processing with Run-time and Syntax Errors

Correcting Errors

Stepping Through a Routine

Continuing Execution From a Breakpoint

Interrupting Execution

Using the Invocation Stack in Debugging

Transferring Routine Control

Displaying Source Code

Correcting Errors in an M Routine

Relinking the Edited Routine

Re-executing the Routine

Using Forked Processes

Summary of GT.M Debugging Tools

Direct Mode is an important tool in GT.M because it allows you to interactively debug, modify, and execute M routines. Direct Mode is a shell that immediately compiles and executes GT.M commands providing an interpretive-like interface. M simplifies debugging by using the same commands for debugging that are used for programming.

The focus of this chapter is to describe the debugging process in Direct Mode, and to illustrate the GT.M language extensions that enhance the process. Command functionality is described only in enough detail to illustrate why a particular command is useful for a debugging activity being described. If you have specific functionality questions about a command or variable, see the “Commands”, “Functions”, or “Intrinsic Special Variables” chapter.

It is also from Direct Mode that you activate GT.M tools used to create M source code. The interaction of M commands used for editing and compiling is described in greater detail within Chapter3: “Development Cycle”.