Experimental Physics and
Industrial Control System

Mark Rivers <[email protected]> · Fri, 15 Aug 2014 13:09:23 +0000

Just to add to the confusion:

> In EPICS LONG means 32-bits, but in 64-bit C it means 64 bits.  You need an array of int not long!

A "long" on 64-bit Linux is 64 bits.  But a "long" on 64-bit Windows is still only 32 bits.  Pointers are 64 bits, but not longs.  The "long long" datatype is 64 bits on Windows (and most other platforms).

Mark

________________________________________
From: [email protected] [[email protected]] on behalf of [email protected] [[email protected]]
Sent: Friday, August 15, 2014 7:32 AM
To: [email protected]; [email protected]
Subject: RE: Problem with creating an array of Long with aSub record

Your problem is a confusing difference in the meaning of "long".

In EPICS LONG means 32-bits, but in 64-bit C it means 64 bits.  You need an array of int not long!
________________________________________
From: David Michel [[email protected]]
Sent: 15 August 2014 12:41
To: EPICS mailing list
Subject: Fwd: Problem with creating an array of Long with aSub record

Oops... please ignore my previous post... somehow pressed the send button by mistake.

===========

Hi All,

I was toying around with an aSub Record to get it to generate an array...

So I've got this code:

static long gen_array(aSubRecord *precord)
{
    long lx=1292;

    long arr[lx];
    long i=0;
    for (i=0;i<lx;i++)
    {
         arr[i] = i;
    }
    memcpy(precord->vala,arr,precord->nova*sizeof(long));

    return 0;
}

and this record:

record(aSub, "MyASubRecord") {
    field(SNAM, "gen_array")
    field(FTVA, "LONG")
    field(NOVA, "1292")
}

Given the value of lx, I would expect to see VALA with 0,1,2,3,4...1291

But I do a caget MyASubRecord.VALA, I get this:

MyASubRecord.VALA 1292 0 0 1 0 2 0 3 0 4... 644 0 645 0

The number of elements is correct, i.e. 1292, but there are 0s interlaced with the correct data ??? I'm sure it's something silly, but I cannot figure it out.

Thanks
David

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Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System