[Gambas-user] gb3: writing variables to a string using a memory stream and pointer

[Kevin Fishburne]

> On Sun, Sep 11, 2011 at 07:40, Kevin Fishburne<
> kevinfishburne at ...1887...>  wrote:
>
>> My code looks like this:
>>
>> ' For writing outgoing UDP data to memory.
>> Public data As String
>> Public mem As Stream
>>
>> ' Create data string for outgoing transaction queue.
>> data = Space(8)
>> mem = Memory VarPtr(data) For Write
>> mem.Begin
>>    Write #mem, (Server.DateCurrent + Server.DateUTC) As Float
>> mem.Send
>> Print data
>>
>> It throws signal 11 on the Print statement.
>>
>> I have two questions. First is this the correct way to write one or more
>> variables to a string in memory, and second what's up with the signal
>> 11? I'm using revision 4094 and will update to the newest revision in a
>> moment.
>

On 09/11/2011 08:13 AM, Jussi Lahtinen wrote:
> Not sure what happen there, but try this:
>
> Public pData As Pointer
> Public mem As Stream
>
> pData = Alloc(SizeOf(gb.Float))
> mem = Memory pData For Write
> mem.Begin
>    Write #mem, (Server.DateCurrent + Server.DateUTC) As Float
> mem.Send
>
> Print Float@(pData)

Thanks everyone for your replies. I'm now using this code ('Data' is a 
string):

' Create data string.
DataPointer = Alloc(8)
Mem = Memory DataPointer For Read Write
Mem.Begin
   Write #Mem, (Server.DateCurrent + Server.DateUTC) As Float
Mem.Send
'Data = Read #Mem As Float
Data = Read #Mem, 8

' Send transaction.
udp.Begin
   Write #udp, id As Byte
   Write #udp, 56 As Byte
   'Write #udp, (Server.DateCurrent + Server.DateUTC) As Float
   Write #udp, Data, Len(Data)
udp.Send

The recipient gets the wrong value for 'Data' when it is converted back 
from a string to a float. It gets the correct value if I use the 
commented "Write #udp, (Server.DateCurrent + Server.DateUTC) As Float". 
Any ideas why I can't write the data stored at DataPointer to the string 
Data?

In case anyone forgot, I need the data to be saved as a string so it can 
be stored in an outgoing network transaction queue, which is an array of 
transaction structures. The Data property of the structure stores 
arbitrary groups of variables so grouping them as a string is the most 
convenient method since there will be up to 255 different transaction types.

-- 
Kevin Fishburne
Eight Virtues
www:http://sales.eightvirtues.com
e-mail:sales at ...1887...
phone: (770) 853-6271