Correcting command entry errors

If you make errors entering a CONTROL command, the audible alarm sounds, and the command appears in the entry area. The location of the cursor indicates the error:

If the error is an invalid operand, the cursor appears under the invalid operand:
```
CONTROL X,N
```
If the error is an invalid erase request, the cursor appears under the first invalid request.
```
CONTROL E,31,19
```
If the CONTROL command exceeds 126 characters, the cursor appears at location 127 in the entry area.

To correct any of these errors, use the procedures described under Changing information in the entry area.

If the system detects an error in a command other than a CONTROL command, it writes the command in the message area with an error message. Follow the procedures indicated for the error message in the MVS™ System Messages books.