Very Computer

  We have a typical problem with ingres.. One application
is developed already in abf (Ingres 4GL). Now we want to intigrate it with
another one..
The old applicatio n is written in esql-c and we are unable to fined a way to call the frame of same
application
through embeded esql program..

Is there any way through you can call the frame of same applica  application through esql C..../.  

We are using Ingres 5.0.

-Waiting for an experts advice..

-Suhas

1) Ingres passes variables from OSL frame to OSL frame/procedure using
   a structure. The underlying C call passes a pointer to this structure
   *not* the variables themselves. Naturally the structure changes in
   size depending upon how many variables are being passed.

2) Therefore, write a dummy piece of OSL that calls the frame you want
   and has the correct number and type of variables, etc. Compile this
   OSL to produce a .OBJ file, but keep the .c file.

3) Examine the .c to see what the structure looks like. Copy the structure
   into your C or ESQL/C program.

4) To actually call the frame in the old application you need to:
   - populate the variables in the structure using C code
   - call the compiled name of the frame. You can find this out by
     examining the .c file created when the frame is compiled.

5) When the user quits out of the frame, the C code needs to access the
   values of any variables that may have been returned by reference.

Be warned that it is tricky and not very flexible eg adding another
variable to the parameter list of the frame is a pain. I haven't looked
to see how Ingres passes quesries to a called frame. I assume that it is
simply another pointer to a structure holding the query added to the
structure holding the list of parameters being passed.

Regards,
--
-------------------------------------------------------------------------------
Bruce Horrocks                                  So much to think about
Surrey, England                                   so little to think with.

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You can specify on the command line an alternate startup frame (form),          

      (in VMS, you translate to other)                                          
          newframe :== $sys$login:myapp.exe -palternate_frame                  

     The -p flag defines the alternate frame name.  As a bonus for              
     INGRES 6.4 users, the -noforms flag will let you run procedures            
      (this will let you run ABF in batch mode).                                

     So, in your ESQL/C program, define the external symbol(command)            
        and execute it via call system (or other means of your choice).        

     Hope this helps you with V5.0, its hidden in various places of the        
     V6.3+ manuals (-noforms is in the V6.3 manuals even though it will        
     only work under V6.4).                                                    

                           Jim