Accessing Main Storage: CORE › Change the Contents of Main Storage › The CHANGE Command (CHG)

The CHANGE Command (CHG)

The CHG command is used to move new data into main storage. The new data is specified in the command after the keyword CHG in character, hexadecimal, packed, or binary format. This command has two formats:

• To move a data string into the main storage area that begins with the first byte of the current CORE display, enter:

  CORE=CHGdata
  

• To move data into main storage beginning at the specified location, enter:

  CORE=loc=CHGdata
  

Specify the data in a CHG command using any of the following formats:

• C'chardata' for character data
• X'hexdata' for hexadecimal data
• P'value' for packed decimal data
• F'value' for a binary fullword
• H'value' for a binary halfword preceded by a plus or minus sign

Replace 'value' with a decimal number, optionally preceded by a plus (+) or minus ( ) sign.

Examples

To place 123 in the first three bytes of storage on display, enter:

CORE=CHGC'123'

To perform the same function as in Example 1, enter:

CORE=CHGX'F1F2F3'

To place the characters 123 in the first three bytes of the data field ACCT NUM defined in the program currently stopped at a breakpoint, enter:

CORE='ACCT NUM'=CHGC'123'

To move the two byte packed decimal value of 100 into the first two bytes of the data field QUANTITY, enter:

CORE='QUANTITY'=CHGP'100'

When entering an apostrophe as part of character data, the apostrophe must be repeated.

To move the name O'HARA into the data area CUSNAME, specify:

CORE='CUSNAME'=CHGC'O"HARA'

Enter any combination of hexadecimal and character data.

To change the value of RECKEY to the name SMITH followed by two bytes of binary zeroes, specify:

CORE='RECKEY'=CHGC'SMITH'X'0000'