The CBL_READ_SCR_CHATTRS routine is one of a set of library routines that facilitate reading and writing attributes on the screen. This routine reads a string of characters and their corresponding attributes from the screen.
CALL "CBL_READ_SCR_CHATTRS" 
    USING SCREEN-POSITION, CHARACTER-BUFFER, ATTRIBUTE-BUFFER,
        STRING-LENGTH 
    RETURNING STATUS-CODE
               	 | SCREEN-POSITION Group item | Group item is defined as follows: 01  SCREEN-POSITION.
    03  ROW-NUMBER      PIC X COMP-X.
    03  COLUMN-NUMBER   PIC X COMP-X.On entry, contains the screen position at which to start reading (the top left corner is row 0, column 0) | 
| CHARACTER-BUFFER PIC X(N). | On exit, this data item contains the characters read from the screen. It must be at least the length specified by STRING-LENGTH. Positions in it beyond that length are unchanged. | 
| ATTRIBUTE-BUFFER PIC X(N). | On exit, this data item contains the attributes read from the screen. It must be at least the length specified by STRING-LENGTH. Positions in the data item beyond that length are unchanged. | 
| STRING-LENGTH PIC XX COMP-X. | On entry, contains the length of the string to read On exit, contains the length of the string read when the end of the screen is reached | 
| STATUS-CODE Any numeric type | Returns 1 if successful, or 0 if not successful | 
This library routine uses SCREEN-POSITION (in row and column coordinates) to determine the location to start the read operation. STRING-LENGTH specifies the length of the string to be read, starting from SCREEN-POSITION. When the routine exits, CHARACTER-BUFFER contains the string of characters read, and ATTRIBUTE-BUFFER contains those characters' attributes.