[Gambas-user] Issues when writing and reading structures

[Brian G]

When a structure containing a string is written the first byte is the length 
But when it is read back as the structure it does not use the length byte but does include the len byte into the string field. 
I am not sure if this is correct or not. 

p.s. is it possible to have varptr return the memory address of the structure as you can assign a pointer to a structure object. 

Is this correct or is it a bug, not sure? But I would like to send structured data to another client and recieve it on that side 
the follow script demonstrates: 

#!/usr/bin/env gbs3 
' Gambas Script File Created 03/21/2023 12:39:45 


Public Struct elevation 
a As Short 
b As Long 
c As Float 
d As Short 
e As String 
End Struct 

Public Sub main() 

Dim a As Elevation 
Dim aa As Elevation 
Dim aaa As Elevation 

Dim p As Pointer = Alloc(10000) 
Dim pp As Pointer = Alloc(10000) 
Dim ppp as pointer = Alloc(10000) 
a = ppp 
a.a = 45 
a.b = 98765 
a.c = 67.456 
a.d = 1 
a.e = "hello a.........." 

aa = pp 
aa.a = 45 
aa.b = 98765 
aa.c = 67.465 
aa.d = 1 
aa.e = "hello aa........" 

Dim f As File 
f = Memory p For Write 
Write #f, a As Variant 
Close #f 

f = Memory p For Read 
aaa = Read #f As Elevation 

Print "Original :"; 
For i As Integer = 0 To 50 
Print Hex(Byte@(ppp + i), 2);; 
Next 
Print 
print "Write :"; 
For i As Integer = 0 To 50 
Print Hex(Byte@(p + i), 2);; 
Next 
Print 
Print "Check Block :"; 
For i As Integer = 0 To 50 
Print Hex(Byte@(pp + i), 2);; 
Next 
Print 

Print "a :";a.a, a.b, a.c, a.d, a.e 
Print "aaa :";aaa.a, aaa.b, aaa.c, aaa.d, aaa.e 
Print "aa :";aa.a, aa.b, aa.c, aa.d, aa.e 
Free(p) 
Free(pp) 
Quit 0 
Catch 
error "Script Error >";;error.text & "\n" & error.where 
end 


"Failure is the key to success; 
each mistake teaches us something" .. Morihei Ueshiba 
Brian G 
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