Calling sequence of builders for a 3277 remote terminal

DFHZCQRT contains a series of comments followed by the patterns. The comment appears as:

     /* * * * * * * * * * * * */
     /*      3277 REMOTE      */
     /* * * * * * * * * * * * */

Shortly afterward is a Declare (DCL) followed by a level-1 name:
```
DCL  1 P145002  STATIC
```
This is the name of the pattern that drives the build process for a 3277 remote terminal.
- DFHBSTZ is indicated to be the first builder called.
- One pattern is used to drive the building process.
- 18 subpatterns are to be used.
- Three of these 18 subpatterns each call one additional pattern.
- The terms “pattern” and “builder” mean the same thing. Therefore:
```
DFHBSTZ  +  DFHBSxx  +  DFHBSxx  =  22
  (1)    +    (18)   +    (3)    =  22
 pattern +    sub-   +  sub-sub- =  22
             patterns   patterns
```
  Thus we have to go through 22 builder modules to build a 3277 remote terminal.
Go to the cross-reference at the back of the dump and find where P145002 is defined in assembler language. Go to that address.
This states that the first builder to be called is DFHBSTZ. This is the main one.
Drop down to the 2-byte fields that follow: these state the names of the builders that are to be called, in sequence (18 should be listed).
The first one is IAATZ1 which does not sound familiar:
- Go to the cross-reference at the back of the dump, look up IAATZ1, and go to where it is defined.
- You see that this is DFHBSTZ1.
- You can also see a close resemblance between IAATZ1 and DFHBSTZ1, but do not count on this to be always true.
Now you know that the second builder to be called is DFHBSTZ1.
The next two builders to be called are IAATCV (DFHBSTV) and IAATCB (DFHBSTB).
The fifth builder to be called according to the pattern needs to be looked at:
- The pattern says that IACTZ3 should be called.
- When you go to where IACTZ3 is defined, you find that this is DFHBSIZ3.
- You also see that DFHBSIZ3 calls IAATM.
- Look up IAATM and you see that it is DFHBSTM.
- This is a sub to a subpattern, and this is how nesting of builder calls occurs.
- Thus, DFHBSIZ3 calls DFHBSTM when building a local 3277.
- DFHBSTM accounts for one of the “other” three mentioned in step 2.
If you continue through this pattern, you can identify the names of the 22 builders that would be called to build a 3270 local TCTTE.
Here is the complete list, in order, of the builders that are called:
```
1  DFHBSTZ         12 DFHBSTH
2  DFHBSTZ1        13 DFHBSTI
3  DFHBSTZV        14 DFHBSTS
4  DFHBSTZB        15 DFHBSTT
5  DFHBSIZ3        16 DFHBSTZA
6  DFHBSTM         17 DFHBSTP3
7  DFHBSTB         18 DFHBSZZ
8  DFHBSIB3        19 DFHBSTB3
9  DFHBSTO         20 DFHBSTZE
10 DFHBSTC         21 DFHBSZZV
11 DFHBSTE         22 DFHBSTZ3
```
A look at Pattern Trace supports this flow. Note that the first ZCP TBSB(P) BUILD and its matching return (the return has no builder suffix) should be ignored.