I'm trying to write a C-language function to be compiled into a shared module to be loaded by Postgres. In it, I have the OID of a function and I need to get information from the
pg_proc table.
So far, I have:
HeapTuple procTuple;
Form_pg_proc procStruct;
procTuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcoid));
if(!HeapTupleIsValid(procTuple))
ereport(ERROR, errmsg("cache lookup failed for function %u.", funcoid));
procStruct = (Form_pg_proc) GETSTRUCT(procTuple);
I can get fields like procStruct->prokind and procStruct->proretset.
However, I get a compiler error when I try to access procStruct->proargmodes. I know that this is because this field is in the CATALOG_VARLEN block which makes it invisible to the compiler.
What is the proper way to get this field?
-Ed