LINE macro

Use the LINE macro to describe both switched and nonswitched communication lines to IMS. The LINE macro provides the address and characteristics of one line in the line group specified by the LINEGRP statement.

The LINE macro statement describes communication lines. If the line described has only one terminal attached, only one TERMINAL macro instruction is included after the LINE macro instruction. Multiple TERMINAL macro instructions are included if the description is for a multidrop line. For nonswitched lines, multiple NAME macro instructions can be included after each TERMINAL macro instruction that follows a LINE macro instruction. Each LINE macro instruction must be followed by at least one TERMINAL macro instruction.

Dynamic definition

Communication lines cannot be dynamically defined.

Supported environments

The LINE macro can be used in the DB/DC and DCCTL environments.

Syntax

All lines

Read syntax diagramSkip visual syntax diagramLINE,BACKUP=4XNO

All lines except spool

Read syntax diagramSkip visual syntax diagram,ADDR=( cuu1, ccu2)

Disk, tape, and spool lines only

Figure 0.
Read syntax diagramSkip visual syntax diagram,BUFSIZE=( number, number)

Positional parameters

The LINE macro does not include positional parameters.

Keyword parameters

To find which parameters apply to your IMS configuration, refer to Selecting the appropriate macros to define your system.

ADDR=
Specifies the address of the communication line as defined in the Transmission Control Unit. The address value is three or four hexadecimal digits between 0000 and FFFF. All line addresses specified in the system definition must be unique values. This operand is used only to generate IMS DD statements for cataloged procedures. It is not allowed if the terminal is a 3270 local. This operand is not required for SPOOL line groups.

This operand is ignored for UNITYPE=PRINTER when a JES spool data set (SYSOUT=X) is to be used rather than a local printer. When XRF is used, a second optional device address can be specified with the ADDR keyword.

BACKUP=
Specifies (for XRF only) the control of the automatic restart after takeover. Use only when HSB=YES is specified on the IMSCTRL macro.

X is a numeric integer from 1 (lowest) to 7 (highest), inclusive, that specifies the priorities for reestablishing the session. If the entire keyword or the operand is omitted, the default is 4. Specifying BACKUP=NO suppresses the automatic restart of the devices after a takeover.

BUFSIZE=
This operand is only valid for DISK, TAPE, and SPOOL lines.

For DISK, TAPE, or SPOOL lines, this operand is used to specify, in bytes, the maximum output buffer size to be used for the line. The operand is required. The minimum specification is 16; the maximum specification is 32 760.

Use of SYSIN local card reader: When the DD statement for a line (specified in the LINEGRP macro statement as UNITYPE=READER) does not allocate a card reader device, the following conditions apply:
  • If IMS is running as a batch program, the DD statement referring to the line must contain DCB=BLKSIZE=80.
  • If IMS is running as a system task, the SYSIN test stream must be placed in a sequential data set with the DCB attributes RECFM=F and BLKSIZE=80. The SYSIN test stream must be pointed to by a DD statement for a reader line within the IMS procedure.

Although VTAM® requests are priority-ordered by IMS, the active requests can be completed in any order because of internal VTAM conflicts and pacing.