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Making binary files question



Ivo,

It should be noted though that using MvEXPORT in that manner
still results in a line feed character being added to the end of
the binary file. So technically it isn't a way to output a truly
accurate binary version of the file contents.

- Jeff Huber
President, 4TheBest eCommerce Solutions
http://4TheBest.com
[email protected]
Office: 760-742-1469
Cell: 760-445-8454
=20



-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of Ivo Truxa
Sent: Tuesday, April 26, 2005 2:38 PM
To: 'Miva Users'
Subject: RE: [meu] Making binary files question


You do not need any external library at all. Plain old MvEXPORT
works just
fine for exporting any kind of data:

<MvEXPORT FILEfile" FIELDS=3D"l.null,l.null"
DELIMITER=3D"{binaryData}">

There is no limit for the binary data passed through the
delimiter.

As for importing - I would suggest updating to the newly released
v5 and
using the file_read() function.

Ivo
http://mivo.truxoft.com=20


-----Original Message-----
From: Scot Ranney


Thanks for the tip! I completely forgot James released that
thing-=20
looks like it will do what I'm looking for. (insert Burns
"excellent" here)

MvMarkus wrote:
> Hi Scot,
>=20
> (Copernicus) James released a pretty neat library for handling
binary
files.
> I don't know if they can help you (or if you did not already
use them),
but
> if not, you should definitely take a look at them. You can find
them at
the
> open source section of his website (
> <A HREF ="http://www.copernicusllc.com/products/source/)">http://www.copernicusllc.com/products/source/)</A>
>=20
> Markus=20

Making binary files question



Exporting asciichar(0) always worked fine for me, but I did not test it with
VM 5 yet. I hope it was not changed.

As for the trailing 0x0A - at many binary files it won't mind at all, at
others adding couple of ASCII 0 may help. At those files requiring the very
exact match, you would need to use a bit more complicated technique using
MvCALL, simulating file upload (to self). Of course, you can always use an
external tool too (other language, library,...), but that's not easily
portable solution.

As I told, you should first verify if the trailing CR (0A) is any issue at
all in your case, and use the more complicated or less portable techniques
only if needed.

Ivo
http://mivo.truxoft.com


-----Original Message-----
From: Scot Ranney


I've almost got this working, but two problems have risen up that I'm
not sure how to deal with.

The first is a big one- I can't get asciichar(0) or asciichar('0') to
write to the file as hex 00 (some sort of spacer or null).

The other is that the end of the file turns out to always be hex 0A -
I'd like to somehow be able to control whatever is at the end of the file.

I made this to test what works when trying to write a binary file using
the method below:

<MvWHILE EXPR = "{l.index LE 255}">
<MvASSIGN NAME = "l.export" VALUE = "{ l.export $
asciichar(l.index)}">
<MvASSIGN NAME = "l.index" VALUE = "{ l.index + 1 }">
</MvWHILE>

Everything is written to the file correctly except for hex 00 and the
last character which is hex 0A.

Any ideas?

Scot

Making binary files question



Duh- Thanks Ivo. I was testing using the old Miva Mia which does not
allow asciichar(0), but once compiled with, it puts the null character
in there fine. Haven't tested it with VM5 yet.

Thanks again-

Scot

Ivo Truxa wrote:
> Exporting asciichar(0) always worked fine for me, but I did not test it with
> VM 5 yet. I hope it was not changed.
>
> As for the trailing 0x0A - at many binary files it won't mind at all, at
> others adding couple of ASCII 0 may help. At those files requiring the very
> exact match, you would need to use a bit more complicated technique using
> MvCALL, simulating file upload (to self). Of course, you can always use an
> external tool too (other language, library,...), but that's not easily
> portable solution.
>
> As I told, you should first verify if the trailing CR (0A) is any issue at
> all in your case, and use the more complicated or less portable techniques
> only if needed.
>
> Ivo
> http://mivo.truxoft.com
>
>
> -----Original Message-----
> From: Scot Ranney
>
>
> I've almost got this working, but two problems have risen up that I'm
> not sure how to deal with.
>
> The first is a big one- I can't get asciichar(0) or asciichar('0') to
> write to the file as hex 00 (some sort of spacer or null).
>
> The other is that the end of the file turns out to always be hex 0A -
> I'd like to somehow be able to control whatever is at the end of the file.
>
> I made this to test what works when trying to write a binary file using
> the method below:
>
> <MvWHILE EXPR = "{l.index LE 255}">
> <MvASSIGN NAME = "l.export" VALUE = "{ l.export $
> asciichar(l.index)}">
> <MvASSIGN NAME = "l.index" VALUE = "{ l.index + 1 }">
> </MvWHILE>
>
> Everything is written to the file correctly except for hex 00 and the
> last character which is hex 0A.
>
> Any ideas?
>
> Scot
>
>