Re: ???registrar(function_name)

[Tim Mooney <mooney@aps.anl.gov>]

Andrew Johnson wrote:
> Liyu, Andrei wrote:
>
> >     As I understand Application Developer's Guide 6.8 I can register
> > function and call it from iocsh (ioc shell).
> >
> >     Ok. I build IOC (windows, epics 3.14.7, MVC++.NET) from example
> > template. Start it ... get
> >
> > ">epics"
> > type "asSub" or "asSub()"
> >
> > and read
> > "command asSub not found"
> >
> > What is wrong?
>
>
> A registrar(function) entry in a DBD file does not automatically 
> register a command with the IOC shell itself, it just arranges for the 
> named function to be called during the IOC's startup process.  The 
> registrar function can then perform any actions you wish to take place 
> at that time, including registering new iocsh commands (for which you 
> have to provide additional information in C code).
>
> See the various files in the <base>/src/iocsh/ directory for examples of 
> the command tables and the related call to iocshRegister() that you have 
> to make to add a new command.  We really should have an example of how 
> to do all this in the example template, but we don't appear to at present.

There are tons of examples in synApps.  Here's an excerpt from save_restore.c:

#include	<epicsExport.h>
#include	<iocsh.h>
...
int request_manual_restore(char *filename, int file_type); {
    <code that implements the function>
}
...
IOCSH_ARG       request_manual_restore_Arg0    = {"filename",iocshArgString};
IOCSH_ARG       request_manual_restore_Arg1    = {"file_type",iocshArgInt};
IOCSH_ARG_ARRAY request_manual_restore_Args[2] = 
{&request_manual_restore_Arg0,&request_manual_restore_Arg1};
IOCSH_FUNCDEF   request_manual_restore_FuncDef = 
{"request_manual_restore",2,request_manual_restore_Args};
static void     request_manual_restore_CallFunc(const iocshArgBuf *args) 
{request_manual_restore(args[0].sval,args[1].iva
...
void save_restoreRegister(void)
{
   ...
    iocshRegister(&request_manual_restore_FuncDef,
                  request_manual_restore_CallFunc);
   ...
}

epicsExportRegistrar(save_restoreRegister);

-------------------

The .dbd file specifies the registrar function as follows:

registrar(save_restoreRegister)

--
Tim Mooney (mooney@aps.anl.gov; 630-252-5417)
Advanced Photon Source
APS Operations Division
Beamline Controls & Data Acquisition Group