You should start with the "main.c" ususally installed in the /usr/share/yumapro/src/db-api-app directory.
Read the documentation in the Server Overview Manual
The code snippet I attached in DB-API-Init-Code-Snippet.txt is basically patterned after your main.c in /usr/share/yumapro/src/db-api-app directory.
There are a couple of items I see from the Makefile supplied in that directory that are missing in my installation of your SDK. For one there is this refererence to a library, sendbuff, that I am been unable to locate in any Open Source or Linux Distribution:
LIBS = -lyumapro_db-api \
-lyumapro_ycontrol -lsendbuff \
-lyumapro_ncx -lxml2 -lz -lm
For the other, there are references to subsys-pro library objects for which I cannot locate within the YumaWorks SDK installation:
LOBJS = $(SUBSYS_TARGET)/subsystem.o
LOBJS += $(SUBSYS_TARGET)/subsys_util.o
If I attempt to build the db-api-app using this Makefile, I get the following error:
...share/yumapro/src/db-api-app> sudo make all
Compiling in C++11 mode
make: *** No rule to make target 'procdefs.h', needed by '../../target/db-api-app/main.o'. Stop.
As I previously mentioned, I am able to compile and link my test application without these referenced library or library objects using the specified APIs from the main.c for db-api-app along with using the specified libraries from above.
It is obvious I am missing something in my development environment to pull in the necessary subsys-pro elements required for registering the DB-API service and to compile the test program for db-api-app.
I have tried running the db-api-app program installed in /usr/bin and I see from the netconfd-pro server.log the DB-API service is being registered from this application:
agt_ycontrol: Got <ycontrol> message:
DB-API: enter service function
DB-API: enter subsys_request
ycontrol_msg: sending server-response # 1 for db-api
<?xml version="1.0" encoding="UTF-8"?>
Following the steps described in the online documentation for the YControl initialization and DB-API Service Registration, I am unable to get the DB-API Service ready via the function call, db_api_service_ready, within a test program I created.
Please see the attached files which document the test program, the program output, netconfd-pro configuration setup (bundle and module names removed), netconfd-pro server log (debug4), and strace output from the test program.
YumaPro SDK Basic installed is 21.10-5-1fcb and this is running on RHEL 8.6.