gtps4m1wSystem Generation

Loaders

SIP stage II will create and list the required MVS Job Control language (JCL) and input to run the offline TPF loader for the loader general file (TPFLDR with PARM='ALDR'). Users must actually run this MVS job. The output of SIP is placed into a named PDS member LOADDECK of the source library for access by the user.

Note:
SIP also creates and lists the load list of E-type programs. This is placed in PDS member PARSxx, where xx is the version number of the current release for domestic customers or where it is the version number of the World Trade load list. (USA or WTC is specified on the USER parameter of the CONFIG macro).

Once the online system has been loaded as a result of the load to the loader general file, the user will often find it necessary to either reload certain programs or to load additional programs. Two facilities are provided: the E-type loader and the auxiliary loader. Associated with these program loaders, there is also a system data loader that is used to load data records (pilots) to the online modules.

TPF General File Loader

The TPF general file loader is designed to load the online modules with all the information required before the control program restart sequence (initial IPL) can be executed. The general file loader consists of two segments: the general file loader offline segment and the general file loader online segment.

The general file loader offline segment (ALDR), operating under the control of MVS, creates an IPLable loader general file. The control program is loaded to this general file. Type 'E' application and system programs are link-edited by the loader using the system allocator record and the TPF linkage editor prior to being loaded to the general file. The JCL and data required to create the initial loader general file is generated by SIP.

Once the offline segment has successfully loaded the loader general file the latter is IPLed. Now the system is under the control of TPF.

The IPL program loads programs to main storage from the loader general file as a result of the IPL. The control program, keypoints, startup programs, FACE table, core-resident application programs, etc., and the general file loader online segment (ACPL) are brought into main storage. If this is an online module load operation, the general file loader online segment takes control at this point and loads programs to the online disk modules using the loader general file as input.

The general file loader can also patch programs as it is loading them. By the appropriate choice of control cards the general file loader will load any or all items required.

E-Type Loader

The E-type loader allows a user to load an unlimited number of E-type (or real-time) program segments onto the online system while the system is operational in any state. Loadsets, which are groups of programs to be loaded, are created offline and then passed to the online system using a tape, general data set, virtual reader, or user-defined device. The offline process is run by submitting JCL that runs the offline E-type loader segment (OLDR). The E-type loader package requires that #OLDx (where x corresponds to a program area) fixed file records be allocated for use as online directory records and program records. For example, if #PROG4 programs are being used, #OLD4 records must be allocated.

Auxiliary Loader

The auxiliary loader allows a user to load the control program, keypoints, E-type programs, and the E-type start-up program segments to an inactive image of TPF. The TPF system can be in any system state. The offline auxiliary loader creates a TLD tape, which contains a tape directory and the programs to be loaded. The auxiliary loader requires the allocation of certain fixed file records for use as an online directory.

Data Loader

The data loader loads pilot system data, which are located on the SDF tape, to the online disk modules. Pilot tapes are created by either the system test compiler (STC) or the SNA table generation process (see System Test Compiler and Communication Pilot Record Generation).

Use the ZSLDR command to activate the data loader and load the pilot tape. If the ID of the pilot tape is N, the TPF system can be in any state. If the ID of the pilot tape is not N, the TPF system must be in 1052 state. You can also activate the data loader after the general file loader online segment has been loaded (see TPF General File Loader).

Note:
If the pilot being loaded contains global records, you must re-IPL the system to get these records into main memory.

See TPF System Installation Support Reference for more information about loaders. See TPF Operations for more information about the ZSLDR command.