What is the use of DSECT parameter in BMS
- DSECT is the parameter used for creating a symbolic map.
- The TYPE=DSECT assembly is used to produce a series of data structures, collectively called the symbolic map set.
- The output of a TYPE=DSECT assembly is a series of data structures, coded in the source language specified in the LANG option. There is a structure for each map used for input, called the symbolic input map, and one for each map used for output, called the symbolic output map.
- Symbolic map sets are used at compile (assembly) time. You copy them into your program, and they allow you to refer to the fields in the maps by name and to pass the variable data in the form dictated by the physical map set.
- Symbolic map sets are typically stored in the library your installation defines for source code that gets copied into programs. Member names are typically the same as the map set names, but they need not be.
- You need the TYPE=DSECT assembly before you compile or assemble your program. You can defer the TYPE=MAP assembly and link-edit until you are ready to test, because the physical map set is not used until execution time. But, you must do both eventually, many installations provide a cataloged procedure to do this automatically.
- The procedure copies the source file for the map set and processes it once using TYPE=MAP and again using TYPE=DSECT. You also can use the SYSPARM option in your assembler procedure to override the TYPE value in a particular assembly.
BMS
- BMS is known as Basic Mapping Support. An application consists of formatted screens which act as a link between the terminal and the CICS programs. For communication to occur between the terminal and the CICS programs, we use CICS terminal input/output services. We use BMS to create screen designs with proper positions and attributes. Following are the functions of BMS,
- BMS acts as an interface between the terminal and the CICS programs.
- The design and format of the screen is separate from the logic of application.
- BMS makes the application hardware independent.