GCMD call
The Get Command (GCMD) call retrieves
the response segments from IMS TM
when your application program processes IMS commands
using the CMD call.
Format
| Call Name | DB/DC | DBCTL | DCCTL | DB Batch | TM Batch |
|---|---|---|---|---|---|
| GCMD | X | X |
Parameters
- i/o pcb
- Specifies the I/O PCB, the first PCB address in the list that is passed to the program. This parameter is an input and output parameter.
- aib
- Specifies the application interface block (AIB) that is used for
the call. This parameter is an input and output parameter. The following fields must be initialized in the AIB:
- AIBID
- Eye catcher. This 8-byte field must contain DFSAIBbb.
- AIBLEN
- AIB lengths. This field must contain the actual length of the AIB that the application program obtained.
- AIBRSNM1
- Resource name. This 8-byte, left-justified field must contain the PCB name IOPCBbbb.
- AIBOALEN
- I/O area length. This field must contain the length of the I/O area that is specified in the call list.
- i/o area
- Specifies the I/O area to use for this call. This parameter is an output parameter. The I/O area must be large enough to hold the largest segment passed between the program and IMS TM.
Usage
When
you issue a CMD call, IMS TM
returns the first command response segment to the application program's
I/O area. If you are processing commands that return more than one
command response segment, use the GCMD call to retrieve
the second and subsequent command response segments. IMS TM returns one command response segment to
the I/O area of your application program each time the application
program issues a GCMD call. The I/O area must be
large enough to hold the longest message segment expected by your
application program. IMS allows
a maximum segment size of 132 bytes (including the 4-byte LLZZ field).
The CMD and GCMD calls
are typically used to perform functions that are usually performed
by someone at a terminal. These programs are called automated operator
(AO) applications.
PCB status codes indicate
the results of a GCMD call. The status codes are
similar to those that result from a message GN call.
A QD status indicates that there are no more segments in the response.
A QE status indicates that a GCMD call was issued
after a CMD call that did not produce response segments.
A blank status ('bb') indicates that a segment was retrieved successfully.
Restrictions
The AIB must specify the I/O PCB for this call.
Any AO application that uses this call must be authorized by the security administrator.
You
cannot issue a GCMD call from a CPI-C driven application
program.
This call is not supported in an IFP, or non-message driven BMP.