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i want to download a .jpg but as it is binary it will contain a 0 at some point. so if i use lstrlen to get its length then write it to a file it wont write the whole file and if i use lstrcat it will only append up until a 0. so how do i get the recv'd data into a file???

the only way i can see to do this is too write it to a file with writefile using the return value of recv as the number of bytes to write. but i have to dl .txt's too, but i dont want to write them to a file - just hold them in memory and i was hoping i could just invoke the same routine for both.

thanks for any help.
skud.

it is possible :)
maybe i am bad at explaining or you misunderstood.
heres my code:

invoke CreateFile, addr temppicname, GENERIC_WRITE, FILE_SHARE_READ, 0, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, 0
mov filehand, eax

xor eax, eax

recv_more:

invoke WriteFile, filehand, addr recvbuff, eax, offset nobytes, 0

invoke recv, sock, addr recvbuff, 1024, 0
cmp eax, 0
jne recv_more

invoke CloseHandle, filehand
invoke closesocket, sock

; --------------------------------------------------------------

this works, but i was hoping i could have the same one for normal text and binary. do .jpg's not have a header? i thought this would result in the header and the picture being in the file, but when i ran the pic it opened in PSP fine. this was the reason i did not use this method in the first place. what i want to do is to download the picture and then view it in my own little viewer. do i have to actually write out the file to do this or can i just keep it in memory? and how do i keep it in memory if it stops at a 0?? i have no experience with anything graphical so to make a .jpg viewer is a big step for me ;)

thanks.
skud.

skud: I should have made the quote better, I didn't mean it's not possible to do it like you showed in your second post, I meant that it isn't possible to do it the same as with text without any changes..because of the nulls

But your method is perfectly fine.. You can do it in memory as well. Normally the server will give you a 'content-length' header back when you request a resource, allocate the amount of memory indicated by that header, then add everything to that piece of memory instead of to the file.
In some occations (not likely for images, but for scripts etc), this header may be not available, then you should receive data until the connection is closed. Problem here is that you don't know the size before you start downloading... I'd suggest variable (reallocatable) memory for this.
But for images, this is a rare occasion so just stick to content-length.

Thomas

Assuming you can parse the http header and content-length, this is the code:

.data?

contentLength dd ?

pMem dd ?



.code

;assuming contentLength is initialized here



invoke GlobalAlloc, GMEM_FIXED, contentLength

mov pMem, eax

mov edi, eax  ; edi is pointer to new mem

xor esi, esi ;esi holds number of bytes already downloaded



recv_more: 



; receive max 1024 bytes at a time:

mov eax, contentLength

sub eax, esi

cmp eax, 1024

ja @F

mov eax, 1024

@@:



;receive bytes:

invoke recv, sock, edi, eax, 0 



cmp eax, SOCKET_ERROR

je @error



add esi, eax ;update number of bytes downloaded

add edi, eax ;update pointer to next piece



cmp eax, 0 

jne recv_more 



cmp esi, contentLength

je @done

; if you get here, the server has closed the connection but

; the file wasn't fully downloaded (downloadedBytes != contentLength)

; show error or something





@done:

; file is downloaded, pMem points to file, contentLength holds length

; when you're done with the buffer, deallocate it:

invoke GlobalFree, pMem



@error:

; error handling here (WSAGetLastError)

I've written it without testing but you'll get the idea.

Thomas

What header do you mean exactly? the http header? like this:

HTTP/1.0 200 OK
Content-type: image/jpeg
Content-length: 34902 etc.

JPEG data starts here

You shouldn't leave that header in the file. It won't be a valid jpeg file then.. However I think PSP will be flexible in this and just look for the magic word at the start of a JPG header, and skipping all that precedes it...
If this is your case, just don't add data to the buffer until you've received two CRLFs. If you mean something else, please explain a bit more..

Thomas

I'm not sure if this is what you want... but you can use the 'URLDownloadToFile' function in urlmon.. it does all the 'work' of taking out the headers for you.