Reference Guide > O Routines > ON_ERROR_GOTO Procedure
  

ON_ERROR_GOTO Procedure
Specifies a statement to jump to if an error occurs in the current procedure.
 
note
If both ON_ERROR and ON_ERROR_GOTO appear before the line in the code that creates the error condition, the ON_ERROR_GOTO takes precedence.
Usage
ON_ERROR_GOTO, label
Input Parameters
label—The name of a label statement to jump to.
 
note
Do not put a colon after this parameter.
Keywords
None.
Discussion
The ON_ERROR_GOTO procedure transfers program control to the point in the program specified by the label parameter after an error occurs. The label parameter specifies a label, which is an identifier followed by a colon. A label may exist on a line by itself. Labels are explained in the PV‑WAVE Programmer’s Guide.
 
note
The name null has a special use with this procedure. If the label name is null, the effect of ON_ERROR_GOTO is canceled and normal processing continues.
If an error occurs, an error code is stored in the system variable !Err. In addition, the text of the error message is stored in !Err_String.
Example
This example demonstrates how ON_ERROR_GOTO is used to control program flow after an error is detected.
PRO on_error_goto_ex1
   ; If an error occurs here, go to the
   ; statement label Proc1_Failed.
   ON_ERROR_GOTO, Proc1_Failed
   ; The effect of ON_ERROR_GOTO is canceled,
   ; normal error processing is in effect.
   ON_ERROR_GOTO, null
   RETURN
   Proc1_Failed:
      PRINT, !Err, !Err_String
END
See Also
ON_ERROR

Version 2017.0
Copyright © 2017, Rogue Wave Software, Inc. All Rights Reserved.