GT.M provides a number of debugging features. These features include the ability to:

The following table summarizes the GT.M language extensions that facilitate debugging.

GT.M Debugging Tools

EXTENSION

EXPLANATION

ZBreak

Establishes a temporary breakpoint, with optional M action and/or activation count.

ZContinue

Continues routine execution from a break.

ZEDit

Invokes the UNIX text editor specified by the EDITOR environment variable.

ZGoto

Removes multiple levels from the M invocation stack and transfers control.

ZLink

Includes a new or modified M routine in the current M image; automatically recompiles if necessary.

ZMessage

Signals the specified condition.

ZPrint

Displays lines of source code.

ZSHow

Displays information about the M environment.

ZSTep

Incrementally executes a routine to the beginning of the next line of the same type.

ZWRite

Displays all or some local or global variables.

$ZCSTATUS

Holds the value of the status code for the last compile performed by a ZCOMPILE, ZLINK or auto-ZLINK.

$ZEDit

Contains the status code for the last ZEDit.

$ZJOBEXAM()

Performs a ZSHOW "*" to a default file location and name, or the one optionally specified by the argument.

$ZLEVel

Contains the current level of DO/XECUTE nesting.

$ZMessage()

Translates an error condition code into text form.

$ZPOSition

Contains a string indicating the current execution location.

$ZPROmpt

Controls the symbol displayed as the direct mode prompt.

$ZROutines

Contains a string specifying a directory list containing the object, and optionally the source, files.

$ZSOurce

Contains name of the M source program most recently ZLINKed or ZEDITed; default name for next ZEDIT or ZLINK.

$ZStatus

Contains error condition code and location of the last exception condition occurring during routine execution.

$ZSTep

Controls the default ZSTep action.

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