All Questions
4,211
questions
0
votes
0
answers
56
views
Is there a better way of listening socket in infinite loop in PHP?
I have the following code for listening socket for client connections
<?php
$socket = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
$port = "1234";
socket_bind($socket, '192.168.1.1', $...
- 19
2
votes
1
answer
43
views
Socket can't find AF_UNIX attribute
I'm using an Arch Linux machine and trying to run the following code from a Python file.
import socket
import sys
if __name__ == "__main__":
print(sys.platform)
server = socket....
- 371
0
votes
0
answers
31
views
Linux Kernel: How to use all ports and avoid WAIT_TIME sockets?
I am building a script for work where I have to scrape massive IP addresses, something like 50 million.
However, when analyzing my program and machine performance, we notice the following:
At least ...
- 129
0
votes
1
answer
35
views
How does the socket buffer work in Linux?
I'm using python TCP server, and the clients will just send data to the server via sockets. In Linux, there are the buffer size defined for TCP. So does that mean when the client writes to the socket, ...
- 341
0
votes
1
answer
103
views
HTTP persistent connection with poll()
On successfully creating the listening socket, I try to run a block of code on it that should maintain a persistent connection. Here is what I have done so far:
while(1) {
struct pollfd pfds[1];
...
- 155
0
votes
0
answers
87
views
Does connect syscall lead to undefined behavior when using nonblocking sockets?
I’m experiencing a very weird behavior in an SSH-like program I’m writing in C for Linux.
Code Overview
The code is completely nonblocking and designed as a reactor where all fds are registered to a ...
- 316
0
votes
0
answers
26
views
Why is writing a file using Splice slower when done asynchronously?
I'm trying to make a program to write files efficiently from data received in a socket.
My approach here is to use the splice Linux syscall, so I made a quick program to do this, and then I tried ...
- 72
0
votes
1
answer
77
views
Is this a bug in Linux sockets? Receiving an extra IP header in a RAW udp socket
I created a RAW socket with the UDP protocol, sent a packet consisting of a UDP header and data, everything is fine in the PP, the packet is correct.
I also created the same socket in another program, ...
- 121
1
vote
0
answers
58
views
Unexpected TCP connection without server binding the port
I'm trying in a loop to connect to a TCP socket as a client. My expectations are that I should not be able to establish the connnection untill the server binds the socket. However, after arrount 15 to ...
- 11
1
vote
1
answer
109
views
TCP packets don't show up on the server C++
I'm trying to flood a server placed on dstat.cc, but it doesn't work as I expected.
Here's the code
#include <iostream>
#include <thread>
#include <vector>
#include <sys/socket.h&...
- 11
0
votes
1
answer
48
views
bind() fails with ENOENT on Unix Domain Socket in Android NDK intermittently on some devices
I'm working on an Android NDK project where I need to bind a Unix domain socket to a path in the app's internal storage. However, the bind() call occasionally fails with ENOENT (No such file or ...
- 53
0
votes
1
answer
44
views
Reverse name lookup with getnameinfo() doesn't work with custom sockaddr_in6
I wrote the following code and expect it to return the address of google.com. However, it returns me an empty string at the end. What do I need to fix to make it work? getnameinfo() gives me the error ...
- 155
0
votes
0
answers
36
views
Can SO_RCVTIMEO be used for two recvfrom() calls
I have set up a receive timeout like this:
struct timeval tv;
tv.tv_sec = timeout;
tv.tv_usec = 0;
if (setsockopt(sock_temp, SOL_SOCKET, SO_RCVTIMEO, (const char*)&tv, sizeof(tv)) < 0) {
...
- 19
0
votes
0
answers
73
views
How to efficiently send one UDP datagram to 10000 destinations in Linux?
The real scenario:
A UDP server has 10000 UDP clients which connected via public Internet IPv4 addresses.
The server wants to send one UDP datagram (whose payload size is 1024 in bytes) to the 10000 ...
- 41.2k
4
votes
0
answers
75
views
Why getsockopt with SO_SNDBUF for a TCP socket gives a 1/13 of the value at /proc/sys/net/core/wmem_default?
While doing some exercises about sockets, I wrote the code below.
const int socketfd = socket(AF_INET, SOCK_STREAM, 0);
int tcprcvbuf;
socklen_t tcprcvbuflen = sizeof(tcprcvbuf);
...
- 53