while loop in python

[gleaming parcel]

@solid dune

Blocked Web TLDs

To maintain a wholesome and friendly environment we block all links to websites using certain TLDs. Your message has been deleted.

Detected TLD(s)
xxx

[solid dune]

print function wont execute inside while loop
heres my implementation

import socket
from socket import AF_INET, SOCK_STREAM
import struct

with socket.socket(AF_INET, SOCK_STREAM) as cl_sock:
    cl_sock.connect((HOST, PORT))

    # getting the name of file
    name = cl_sock.recv(1024).decode()

    print(f"name received filename: {name}")

    # getting the size of file
    packed_size = cl_sock.recv(8)
    total_buffer_size = struct.unpack("Q", packed_size)[0]

    print(f"size received totalsize: {total_buffer_size}")

    # bcz dynamic allocation sux:(
    bytes_received = bytearray(total_buffer_size)

    print(f"getting akshuall file now pls work")
    # getting the akshual file
    while (x := total_buffer_size) > (y := len(bytes_received)):
        print("working...?")
        chunk_size = min(4096, total_buffer_size - bytes_received)
        chunk = cl_sock.recv(chunk_size)
        bytes_received.extend(chunk)
        # walrus bcz me lazy + no lsp :/
        print(f"almost there {x}/{y}")

    # saving file :)
    with open(name, "wb") as file:
        file.write(bytes_received)

print("script executed successfully")

code works just fine tho

[spice jewel]

You're looping while total_buffer_size is greater than len(bytes_received) but when you create bytes_received you tell it to fill it with total_buffer_size zeros so its length is always equal to total_buffer_size and so total_buffer_size is never greater than len(bytes_received)

And that was a run on sentence...

bytes_received = bytearray()
while total_buffer_size > len(bytes_received):
    print("working...?")
    chunk_size = min(4096, total_buffer_size - bytes_received)
    chunk = cl_sock.recv(chunk_size)
    bytes_received.extend(chunk)
    print(f"almost there {total_buffer_size}/{len(bytes_recieved)}")

You need an empty bytes_recieved for your code to work

[solid dune]

appreciate it

[spice jewel]

Also no need for assignment expressions in your while condition

[solid dune]

yeah i was just coding without anything...

never done that

like without even a type checker or lsp

[solid dune]

i mean len(bytes_received) would be used thrice so why is walrus a bad idea here?

while total_buffer_size > len(bytes_received):
print("working...?")
chunk_size = min(4096, total_buffer_size - len(bytes_received))
chunk = cl_sock.recv(chunk_size)
bytes_received.extend(chunk)
print(f"almost there {total_buffer_size}/{len(bytes_recieved)}")

_ _
ik it isnt much but i was coding without a code editor......

also i thought not doing dynamic allocation would be an option for me since i already know the file size :/

[spice jewel]

The first and second time it's the initial value, the third time its a new value. So if you assign it to y it'll be wrong in the third use

So if you assign it anywhere, assign it in the third use

[solid dune]

ooo yesss it gets evaluated from there

[spice jewel]

bytes_received = bytearray()
y = 0
while total_buffer_size > y:
    print("working...?")
    chunk_size = min(4096, total_buffer_size - y)
    chunk = cl_sock.recv(chunk_size)
    bytes_received.extend(chunk)
    y = len(bytes_recieved)
    print(f"almost there {total_buffer_size}/{y}")

Might actually be faster to just add chunk_size to y

bytes_received = bytearray()
y = 0
while total_buffer_size > y:
    print("working...?")
    chunk_size = min(4096, total_buffer_size - y)
    chunk = cl_sock.recv(chunk_size)
    bytes_received.extend(chunk)
    y += chunk_size
    print(f"almost there {total_buffer_size}/{y}")

[solid dune]

interesting... dont call it y plz

[solid dune]

    rb_list = bytearray(total_buffer_size)

    print(f"getting akshuall file now pls work")
    # getting the akshual file
    start = 0
    while chunk := cl_sock.recv(4096):
        rb_list[start : start + len(chunk)] = chunk
        start += len(chunk)
        print(f"bytes received: {total_buffer_size}/{start}")

btw my whole concept of array is ruined now

its not an array

[solid dune]

btw no dynamic memory allocation here :D_ _

tested it with an image and it worked

valid phyton 💀

  4 barray = bytearray(9)
  3 print(len(barray))
  2 barray[0:3] = 2, 2, 2, 8, 90
  1
 12  print(len(barray))
~

i thought arrays were data structures of fixed len

[solid dune]

tbh ive never seen anyone using streams like that recvin till EOF is the only good practice ig?

[solid dune]

wouldnt matter in my case since its by size of chunk

[solid dune]

bro how is this more efficient

    y = 0
    while total_buffer_size > y:
        chunk = cl_sock.recv(4096)
        rb_list.extend(chunk)
        y += len(chunk)
        print(f"bytes received: {total_buffer_size}/{y}")

this took:
total time taken: 0.008171840978320688
....
while my implementation took:
total time taken: 0.009359975985717028

i mean ive only tested it on an image will try sending the os file through it

[spice jewel]

More efficient than what specifically?

[solid dune]

than this

[spice jewel]

That's doing a copy

rb_list[start : start + len(chunk)] = chunk

So yeah, slow

Extend drops the existing object into the bytearray while using a slice forces the data to be copied over to fill the existing memory that belongs to the bytearray

[coarse stratus]

been too long since I've done python this all just looks like squiggles to me ngl

[spice jewel]

It’s literally python. Read it as if it were plain English and it’ll make sense

[coarse stratus]

bro I speak polish, I can understand English perfectly well

but that....naw

that ain't English, tf is an rb_list

why you gotta abbreviate everything and love the underscores

and when I saw "y"as a variable... bro ima cry

I'm going to my corner, this is just too much for me

[solid dune]

received_bytes_list:)

[coarse stratus]

that's betterrrrrr

should've just written that

[solid dune]

list part was ironic cuz its not really an array imo xD

[coarse stratus]

oh yeah a list in python is just a dynamic array right?

[solid dune]

wbrb_seq?

[coarse stratus]

nah

what is that

rib_ sequence

[solid dune]

list is a type of array yeah otherwise you could do import array

[coarse stratus]

idk I hate static arrays, they made me wanna kill someone

[solid dune]

recevied_bytes_sequence

[coarse stratus]

close

bytes, bits, ribs

[solid dune]

lol

[coarse stratus]

also tf you analysing data for? you making a bomb or smthn?

[solid dune]

i used to think like that

[coarse stratus]

I mean you can always work around static arrays, just make a new one and release the old one and whatever

[solid dune]

its a file transfer 💀

[coarse stratus]

oh

you just downloading shit

or uploading

[solid dune]

ye

both

since its not the full code

[coarse stratus]

aha

[solid dune]

so i did it real transfer and for the extending one its
0.42...
and for the copy one its
-438962.97..... 💀

[coarse stratus]

what are you even transfering

[solid dune]

eh i tested it on an image

[coarse stratus]

aha so uhhhh I assume you just did it cause why not

[coarse stratus]

or you tryna move your hentai stash without anyone looking, I get it been there tok

God if my gf saw me saying that I'd be dead, she's literally right next to me god save me

[coarse stratus]

you got your damn IP in the open like that??

[solid dune]

@spice jewel bro you alive...

[coarse stratus]

wait why tf you.got your ip out like that, yknow having it out won't change anything lol

[solid dune]

not rob have my public ip i dont want him to know what computer im using

[coarse stratus]

like oh wow some is gonna ddos meeee but wait I can just calllllll my isp and they will c**kblock yoy

I mean most people don't know that you can abuse the ntp servers to send terabytes of data per second, thanks a proper fucking ddos

[solid dune]

#💬general

[coarse stratus]

nah nah wait uhhh yeah I got no excuse

ok see you there