Unable to access table using lua after creation of table in C

["Dr Christopher S Kirk" <drcskirk@...>]

Will you be kind enough to point me to examples for the treatment of
tables across the stack for the following case.

I have carefully followed the PIL work on pages 231-234 of 2nd edn PIL.
(Table manipulation).

I seek to create a table in lua and populate it with data, then access
it from 'C' and update (change) values and then to read and manipulate
in lua.

In this case I am creating a lua engine which calls 'C' functions.

I am able to correctly read values from the original lua table (when in
'C') and to manipulate them.  I then wish to store the values (as
changed) back in the lua table for later manipulation in lua.  

I have only found a lua_newtable capability to create a lua table (I can
use lua_getglobal to read an existing table but receive an 'Unknown
Error' when using that to develop a method to store values using
setfield.  So being unable to update an existing table I created a new
table (whilst in 'C' using setglobal) [eg lua_setglobal(L,
"tablename2");] and I could then read it to check it whilst still in 'C'
using [lua_getglobal(L,tablename2");] but then on returning control to
lua I cannot open the new table tablename2 as it is reported as having a
'nil' value (non-existant maybe).

Will you be kind enough to point me to an area where I might resolve
these issues?

Overview:
Open a table and populate in lua
Modify some contents in C
Use a metatable modification to signal when the table has been changed
__newindex
Print out or report using lua after manipulation of incoming data

Object: to replace a callback in a C function with a lua callback-type
function which sends a 'C-structure' to a lua table

Very many thanks

Chris
-- 
Dr Christopher S Kirk

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