bdfp1m2r | Programming Concepts and Reference |
Use this macro to set global variables at assembly time based on specified
block types. You can set the following information:
- Block size
- Maximum next available byte (NAB)
- Control bits.
Format
- label
- is a symbolic name assigned to the macro statement.
- 0
- specifies the processing mode that is used to get the physical block size
and control bits corresponding to the specified block type.
- 1
- specifies the processing mode that is used to get the physical block size,
maximum next available byte (NAB), and control bits corresponding to block
types specified by global variables &SW00WRS and &SW00ARS.
- 3
- specifies the processing mode that is used to get the physical block size,
maximum NAB, and control bits corresponding to the block types specified by
the WRS and ARS parameters.
- name
- is the name of the segment or macro that called the BLKSZ macro. If
an error occurs while processing the BLKSZ macro, the specified name is
displayed in the assembly error message.
- BLKTYP
- specifies the block type for which the physical block size and control
bits will be set.
- WRS
- specifies the prime block type for which the physical block size, maximum
NAB, and control bits will be set.
- ARS
- specifies the overflow block type for which the physical block size,
maximum NAB, and control bits will be set. If you do not specify this
parameter or if you set it to 0, the values set will be the same as those set
for the WRS parameter.
- blktype
- is one of the following block types:
- L0
- specifies a 128-byte block size. Do not use this value when you
specify processing mode 3.
- L1
- specifies a 381-byte block size.
- L2
- specifies a 1055-byte block size.
- L3
- specifies a 4000-byte block size. This block type is available only
in an ALCS environment.
- L4
- specifies a 4095-byte block size.
- L5
- specifies a user-defined size. This block type is available only in
an ALCS environment.
- L6
- specifies a user-defined size. This block type is available only in
an ALCS environment.
- L7
- specifies a user-defined size. This block type is available only in
an ALCS environment.
- L8
- specifies a user-defined size. This block type is available only in
an ALCS environment.
Entry Requirements
If you specify processing mode 1, you must set the assembler global
variable &SW00WRS (and optionally, variable &SW00ARS) to a valid block
type.
Normal Return
- If you specify processing mode 0, assembler global variables are set as
follows for the specified block type:
- Variable
- Set To
- &BLKSZS
- The physical block size.
- &BLKSZPI
- The control bits.
- If you specify processing mode 1, assembler global variables are set as
follows for the block type specified by assembler global variable
&SW00WRS:
- Variable
- Set To
- &BLKSZPS
- The physical block size.
- &BLKSZPN
- The maximum NAB.
- &BLKSZPI
- The control bits.
In addition, assembler global variables are set as follows for the block
type specified by assembler global variable &SW00ARS:
- Variable
- Set To
- &BLKSZAS
- The physical block size.
- &BLKSZAN
- The maximum NAB.
- &BLKSZAI
- The control bits.
- Note:
- If variable &SW00ARS is 0 or not defined, these variables are set to the
same values that were used for &SW00WRS.
- If you specify processing mode 3, assembler global variables are set as
follows for the block type specified by the WRS parameter:
- Variable
- Set To
- &BLKSZPS
- The physical block size.
- &BLKSZPN
- The maximum NAB.
- &BLKSZPI
- The control bits.
In addition, assembler global variables are set as follows for the block
type specified by the ARS parameter:
- Variable
- Set To
- &BLKSZAS
- The physical block size.
- &BLKSZAN
- The maximum NAB.
- &BLKSZAI
- The control bits.
- Note:
- If you do not specify the ARS parameter, these variables are set to the same
values that were used for the WRS parameter.
Error Return
If you specify an incorrect processing mode or block type, an assembler
error (referred to as an MNOTE) with a severity of 8 is issued.
Programming Considerations
Examples
- The following example returns the physical block size and control bits for
an L1 block type.
BLKSZ 0,GRT8SR,BLKTYP=L1
The following assembler global variables will be set by the macro:
- Variable
- Setting
- &BLKSZS
- 381
- &BLKSZPI
- X'00'
- The following example returns the physical block size, maximum NAB, and
control bits for L2 and L4 block types.
&SW00WRS SETC 'L2'
&SW00ARS SETC 'L4'
·
·
·
BLKSZ 1,IR75DF
The following assembler global variables will be set by the macro:
- Variable
- Setting
- &BLKSZPS
- 1055
- &BLKSZPN
- 1019
- &BLKSZPI
- X'10'
- &BLKSZAS
- 4095
- &BLKSZAN
- 4059
- &BLKSZAI
- X'20' (in a TPF system) or X'30' (in an ALCS environment)
- The following example returns the physical block size, maximum NAB, and
control bits for the L2 block type.
BLKSZ 3,IR80DF,WRS=L2
The following assembler global variables will be set by the macro:
- Variable
- Setting
- &BLKSZPS
- 1055
- &BLKSZPN
- 1019
- &BLKSZPI
- X'10'
- &BLKSZAS
- 1055
- &BLKSZAN
- 1019
- &BLKSZAI
- X'10'
Related Macros
None.