Experimental Physics and
Industrial Control System

[email protected] · Mon, 13 Apr 2015 18:15:18 -0500

Hello,

I am trying to use the dbDumpRecords example given in section 14.16.2 to
display a list of records and their fields at IOC initialization. I
included the example code as a function in the main.c code. Actually, the
main.c has also been modified and is now called iocMain.cpp. I am calling
the dbDumpRecords function using *iocshPpdbbase.

The example code I'm using,
****************************************************
void dbDumpRecords(DBBASE *pdbbase)
{
    DBENTRY  *pdbentry;
    long  status;

    pdbentry = dbAllocEntry(pdbbase);
    status = dbFirstRecordType(pdbentry);
    if(status) {printf("No record descriptions\n");return;}
    while(!status) {
        printf("record type: %s",dbGetRecordTypeName(pdbentry));
        status = dbFirstRecord(pdbentry);
        if(status) printf("  No Records\n");
        while(!status) {
            if (dbIsAlias(pdbentry)
                printf("\n  Alias:%s\n",dbGetRecordName(pdbentry));
            else {
                printf("\n  Record:%s\n",dbGetRecordName(pdbentry));
                status = dbFirstField(pdbentry,TRUE);
                    if(status) printf("    No Fields\n");
                while(!status) {
                    printf("    %s: %s",dbGetFieldName(pdbentry),
                        dbGetString(pdbentry));
                    status=dbNextField(pdbentry,TRUE);
                }
            }
            status = dbNextRecord(pdbentry);
        }
        status = dbNextRecordType(pdbentry);
    }
    printf("End of all Records\n");
    dbFreeEntry(pdbentry);
}
**************************************************
This modification is running on a 32 bit Windows 7 machine using EPICS
base 3.14.12.3. The compiler is MS Visual Studio 11.

The code solution compiles without any issues but when I try to run the
IOC it causes the following

Unhandled exception at 0x5C6F1C6E (dbStaticHost.dll) in tcIoc.exe:
0xC0000005: Access violation reading location 0x00000031.

I have also tried several of the other static database functions,
dbDumpRecord, dbDumpRecordType, dbDumpMenu, and I have discovered the
following.

I can use the static database functions to display the record type names,
the record names, and the record fields. But if I try to access the record
fields the IOC will crash. If I use the dbVerify function to test the
record field values I get a bunch of null and not valid output, for
example,

Record type: ai
   Record: test1
    DESC:  (null)
    ASG:  (null)
    SCAN:  Not a valid menu choice
    PINI:  Not a valid menu choice
    PHAS:  not an integer number

etc.

Also, the

void dbDumpRecord(DBBASE *pdbbase,char *precordTypeName,int level);

function fails with the same type of access violation when I have tried
using it. All functions that try to read the record fields fail. However,
if I comment out the offending function calls and start the IOC shell, I
can use dbDumpRecord(pdbbase) at the prompt and it succeeds.

I am a newbie at modifying IOCs so I'm not sure what could be going wrong
when trying to access the records fields. Any help is greatly appreciated.
If I can post any follow up info please let me know.

Thank you in advance,
Doug Lormand

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System