General
Application area: | Data terminal communication; see "Data terminal communication" |
Macro type: | Type O; see "O-type macros" |
Macro description
The SETBF macro enables a user program to change the size of the internal physical I/O buffer for communication with the terminal.
The SETBF macro is ignored in batch mode.
Macro format and description of operands
SETBF |
{size [,N] / (1)} |
size
Size of the buffer (number of characters). 80 <= size <= 3482.
N
Indicates that no change is to be made in the buffer size if the requested size is the same or smaller than the current buffer size.
(1)
Indicates that the user has loaded general register 1 with the size of the buffer desired before issuing the SETBF macro. If the function corresponding to the N operand is required, the complement of the size must be loaded in register R1.
Return information and error flags
R15:
+---------------+ | | | | | | | | | | | |a|a| +---------------+
A return code relating to the execution of the SETBF macro is transferred in the rightmost byte of register R15.
X'aa' | Meaning |
X'00' | Requested buffer allocated |
X'04' | Invalid buffer size specified by the user program |
X'08' | New buffer could not be allocated |