Trying to load an Atari disk image into memory

[rcamp48]

Code: Text: [Select]

1.  

Hi: I am trying to load a headerless binary file into memory (92160 K) , then preattach a header to it, basically load inn an xfs file as binary then write it back out as binary as an atr file.
The code I am using in the above section does not work. All I get is spaces.

Russ

[SMcNeill]

Open "KWEST01B.XFD" For Binary As #1
Get #1, , temp$ 'get the whole array

The problem is with the above -- temp$ is a blank 0 byte string of "" by default, so you're getting 0 bytes from your file.

Open "KWEST01B.XFD" For Binary As #1
temp$ = SPACE$(LOF(1)) 'set temp$ to be the size of the file, if you want to get the whole thing at once.
Get #1, , temp$ 'get the whole array

[Cobalt]

Just what do you have myarray() DIMed as anyhow?
why not just GET #1,, myarray()?
If you know the file size anyway?(and even if you don't you still could)

Code: QB64: [Select]

1. DIM myarray(92176) AS STRING '(or myarray as string *92176, or myarray(lof(1)) as string [after the OPEN] or even myarray(lof(1)) as _UNSIGNED _BYTE)
2. OPEN "KWEST01B.XFD" FOR BINARY AS #1
3. GET #1, , myarray()
4.  

PS, just out of curiosity, do you realize just how big "myarray(1 To 92176) As String * 92176" that array is? 8,496,414,976 bytes!!!
do you really need 8gigs+ to load it?

[tomxp411]

Ok, let's start with: you don't need TEMP$ or the array. You definitely do not want an array of string*92126 objects. That gives you 92126*92126 characters, which is over 8GB.

You should be able to load data straight into a string*, like this:

Code: QB64: [Select]

1. Dim DiskData As String * 92176
2.  
3. Open "KWEST01B.XFD" For Binary As #1
4. Get #1, , DiskData 'get the whole array
5. Close #1
6.  
7. dim Header as string * 32
8. Header = "96028016800000000000000000000000"
9.  
10. Open "KWEST01B.ATR" For Binary As #1
11. PUT #1, Header
12. PUT #1, DiskData
13. CLOSE #1
14.  
15.  

[tomxp411]

Here is a complete example that loads the 92K image, adds the header, and writes back the ATR file with the header.

Code: QB64: [Select]

1. DefLng A-Z
2. Const IMG_LEN = 92176
3.  
4. ''Create test data
5. 'Dim b As _Byte
6. 'b = 0
7. 'Open "KWEST01B.XFD" For Binary As #1
8. 'For i = 1 To IMG_LEN
9. '    Put #1, , b
10. '    b = b + 1
11. 'Next
12. 'Close 1
13. 'Print "File saved"
14. 'End
15.  
16. Dim DiskData As String * IMG_LEN
17.  
18. Open "KWEST01B.XFD" For Binary As #1
19. Get #1, , DiskData 'get the whole array
20. Close #1
21.  
22. Dim Header As String * 32
23. Header = "96028016800000000000000000000000"
24.  
25. Open "KWEST01B.ATR" For Binary As #1
26. Put #1, , Header
27. Put #1, , DiskData
28. Close #1
29.