Questions tagged [socket]
is a data communications endpoint for exchanging data between processes executing within the same host operating system.
394
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sockstat of php-fpm doesn't match config file
I am trying to get a test system up and running under FreeBSD (actually under a TrueNAS jail) using nginx, php and php-fpm. This is the first time I've tried to build such a system, and FreeBSD isn't ...
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5
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How to allocate socket buffer memory from local memory of specific NUMA node
My computer has 2 CPUs, and each node has its local memory. They operate using NUMA architecture. The operating system (O/S) is Rocky Linux 9.1 (x86_64).
Additionally, each CPU is equipped with a ...
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SOCKET auditd hex value meaning
I have the following log messages from auditd. They appear to log calls to socket.
type=SYSCALL msg=audit(05/11/2023 23:19:52.913:2533) :
arch=x86_64 syscall=socket success=yes exit=9
a0=inet a1=...
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Specifiy which SPI interface to use for SocketCAN interface
I am using a Raspberry Pi 4b with Raspberry Pi OS (kernel 5.15) and a custom CAN HAT with 3xMCP2517FD CAN controllers connected to SPI0/1/4 of the Raspberry Pi to communicate to other CAN nodes on ...
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57
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Application server socket won't open in docker on my machine
Introduction
I am developing a proprietary application that uses libevent with libevhtp to create a server socket for http communication.
I wrote a Dockerfile to place this application in a docker ...
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55
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QEMU CAN Bus Emulation; error on socket bind: No such device
The goal is to run following C program in the VM.
int main(int argc, char **argv) {
int s, i;
int nbytes;
struct sockaddr_can addr;
struct ifreq ifr;
struct can_frame frame;
...
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103
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Why is /fd/1 (stdout) a socket?
I'm running a game server as a systemd service, and in the .service file, I see that StandardOutput defaults to journal.
Ihsan@IhsanServerVM:/proc/28617/fd$ file 1
1: symbolic link to socket:[510374]
...
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1
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46
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Sending data with raw socket over gretap
I'm trying to write an IS-IS packet to gretap interface with ISO (0x00fe) protocol type. In this case there is no ethernet header so I'm using raw socket. The gretap always puts 0x6558 as the protocol ...
- 21
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54
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Using chrony with non-root sockets
I'm trying to used chrony in conjunction with a C++ application I'm working on.
Ideally I would like to send information to chrony using sockets rather than SHM, but it seems that chrony can only ...
- 130
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edge triggered epoll missing 0 byte read on close
I'm trying to understand if its possible to use edge-triggered epoll and avoid the need to call recv() to read from an epoll triggered READ event multiple times, every single time...
The epoll manpage ...
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95
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SockFS mount / interacting with UDP & TCP sockets through filesystem
I was reading about SockFS, and I'm wondering why there seems to be no mount driver for it. That is, if SockFS implements the VFS API for UDP and TCP sockets, why is there no userspace filesystem ...
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How is the hardware TX queue selected by default?
NICs may have multiple hardware RX and TX queues, and there are several methods which allow choosing which RX and TX queues are used for a given flow/packet, though most are focused on the RX side.
...
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Process stucked at recvfrom syscall
A process is stucked at recvfrom syscall.
> sudo strace -p 4146278
strace: Process 4146278 attached
recvfrom(9 ...
I looked up under /proc/4146278/fd.
fd 9 seems to be a socket.
> sudo ls -al /...
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Convert a file being downloaded by firefox (.part) into a named pipe?
Slightly unusual usecase: I have a download from firefox which is actually a stream of data. I want to process it in (near) real-time, without saving the data (it's high volume and would fill my drive ...
- 103
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45
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Socket buffer data structure format (from file descriptor to buffer)
I'm trying to learn basic I/O and how kernel manages interface between I/O resources and processes. I got interested in how it manages buffering, and want to ask about sockets as an example. Is the ...
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What would cause a connection refused (wireshark: [RST,ACK]) error?
I have a service running on my RHEL 8 server VM on port 9092. When I send messages to this port from a client, the connection times out. WireShark shows that the server responded with a [RST,ACK], as ...
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242
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What's the default KeepAlive value for a TCP socket in a UNIX-like Docker container?
I am creating a TCP socket as follows:
_socket = new Socket(AddressFamily.InterNetwork,
SocketType.Stream,
ProtocolType.Tcp);
if (Environment.OSVersion....
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49
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Is there a way someone can read arrays of bytes which I send with java sockets while using TLS 1.2?
If anyone can answer me pls I just need an anwer. I know thus isn't maybe right place for this question
I created chatting app with sockets in Java 8 and i use TLS 1.2 My question is: Is there any way ...
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66
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cyrus imap does not start lmtp tcp socket, error message: Servname not supported for ai_socktype, disabling lmtp
Problem:
When starting cyrus imap with the following line in /etc/cyrus.conf:
SERVICES {
...
lmtp cmd="lmtpd -a" listen="[192.168.50.100]:lmtp" prefork=1 proto=tcp4
}
...
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37
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Auditd - SOCKADDR - AF_LOCAL - Parsing issues
(Cross posted)
I set out to parse an auditd log entry containing a SOCKADDR event. I am running into issues with additional data and trying to identify where its coming from and the structure of it.
...
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129
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Linux SO_RCVLOWAT being violated by epoll according to FIONREAD
The more traditional way of dealing with sockets is to have a buffer per connection, and to incrementally read as many bytes as possible once the socket becomes readable.
With a framed protocol ...
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1
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529
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Selinux php-fpm httpd and mariadb socket connection
New note with important details
I just ran a few version tests and resulted in the following:
Alright, here’s my latest update:
10.5 works
10.6 doesn’t
10.7 works
10.8 work
etc.
I was hoping to use ...
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47
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After enabling ETF qdisc packets are only sent for a few seconds
I have two computers that are connected via an Ethernet cable with Ubuntu 22.04 installed on them. I have a client on computer A) which is sending UDP packets to a server on computer B). I am ...
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450
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How to create a dummy/Virtual network interface programmatically using C/C++ in Linux
I am new to socket programming .
Recently i have been looking at the codes here in this platform , such as:
https://stackoverflow.com/questions/5094495/programmatically-enable-disable-unix-network-...
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1
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336
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Writing to unix socket file as fast as possible
I'm trying to write with perl to a unix socket file as fast as possible but failing on full message buffer. I tried autoflush and manual flush without success.
use IO::Select;
use IO::Socket::UNIX;
...
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1
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154
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Number of open sockets in /proc/pid/fd does not agree with netstat
I'm running into a weird socket issue when running my own crawler. It opens and cloees a lot of TCP sockets rapidly due to the protocol design. It's something I have to live with. I'm very sure in ...
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657
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Find my display socket
I'm trying to find my display socket so I can pass it to a container. I expect it to either be in /tmp/X11.unix or /run/user/xxxx/wayland-0, but neither exist. I'm using KDE Plasma with X11.
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131
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websocat server with timestamp
I am running websocat (https://github.com/vi/websocat/) on macOS in server mode for debugging purposes.
I would like to display a timestamp on every incoming message.
However: I am struggling with ...
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2
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366
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Why is there less latency and jitter when there is additional high bandwidth traffic between two computers with Ubuntu 22.04 installed on them?
I have two computers that are connected via an Ethernet cable with Ubuntu 22.04 installed on them. I have a client on computer A) which is sending UDP packets to a server on computer B) and I am ...
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1
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260
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How does a telegram bot work in Linux?
I wrote a simple telegram bot and it works great without conflicting with my firewall. But my question is this, in the firewall I have ports 80 and 443 allowed for my site, but when I write a TCP ...
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Socat serial to tcp for authorized users
Hello everyone I hope you doing well
I have a raspberry pi and I kind need a serial port server which can access from internet
Now I use socat command like bellow on my raspberry and from putty on ...
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ENOSYS (_SIGN 38) while bind() raw socket in MINIX 3
Code Snippet:
// Open internal socket
int raw_internal_1 =0;
raw_internal_1 = socket(AF_INET, SOCK_RAW, IPPROTO_UDP);
if(raw_internal_1 < 0){
perror("Error[01]: ...
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1
answer
46
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EPROTOTYPE (_SIGN 41 ) while creating raw socket() in MINIX 3
The following is my code snippet that is producing EPROTOTYPE error, aka, Protocol Wrong Type for Socket.
I checked for the headers in /usr/include in MINIX 3, sys/socket.h contains definitions for ...
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1
answer
116
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Facing difficulties sending bytes containing white spaces python irc bot
Trying to make a basic irc bot in python (3.9.2) that can response specific commands when invoked. It works although when a response contains whitespace or a space, only the first word gets displayed ...
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IP_MINTTL is not working on raw socket
We are implementing TTL security feature to OSPF. As part of this, We need to validate the incoming ospf packets based on ttl value.
For this, we are using IP_MINTTL socket option to validate the ...
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0
answers
148
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Turn a script do while to a systemctl service to intercept a tcp connection state
I made a little script that refresh browser, when web-server is down and connection is lost, with an infinite loop do/while true.
I want to turn it in a service for a better and clean solution.
The ...
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149
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is it possible to pipe websocat OR wscat to a php script and echo
The question is about doing computation on live data that arrives via a high speed wss websocket... to show it live on the terminal.
When I try to pipe websocat OR wscat to a simple .sh or a .php I ...
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211
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SSH or telnet as an unpriviledged user leads to 'socket: Permission denied' error
I'm running a strange 3.0.35 heavily patched kernel on an embedded device (Kobo eReader). Maybe it partly explains this issue.Basically:
kobo:/$ ssh root@127.0.0.1
socket: Permission denied
ssh: ...
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334
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get data from socket on port
I have a specific service that sends data on port 5555. I need to open socket on shell unix to listen on this port and print output on shell. Service is deployed as docker container.
So, I run ...
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310
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Is 2 pipes more expensive than 1 socketpair?
Suppose I want to launch a co-process and attach its standard input and output to the main process, what we have here are 2 options:
call pipe(2) and create 2 pipes, and attach them separately to the ...
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Linux: Are sockets always on device 00:08?
After opening up a socket in a C program, I ran fstat on it and printed out the major and minor device numbers. I got a major number of 0 and a minor number of 8. Looking at the Linux kernel ...
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167
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dovecot: Force TCP socket disconnect on imap login failure?
I'm running dovecot 2.2.13 under Debian 8.
I'd like to force an immediate TCP socket disconnect after any imap login attempt that fails.
Right now, if invalid credentials are supplied during an imap ...
- 455
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77
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XDMCP locally using Unix sockets
Is there any way to start a XDMCP session, say with Xephyr in LightDM, locally through Unix Sockets instead of IP?
For performance I was wondering if, somehow, I can avoid any network stack working ...
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1
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302
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websocat / wscat save a new file per seconds
This question is about saving a wss:// stream into multiple files... while execution (NOT AFTER)
EXAMPLE :
websocat "wss://stream.binance.com:9443/ws/btcusdt@depth" > /path/$(date +%s)....
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96
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systemd service file closing socket
I need to run a C++ binary with systemd.
When I execute the binary directly or with a bash script it runs fine for days:
nohup ./testbinary &
./test.sh
test.sh:
#!/bin/bash
LD_LIBRARY_PATH="...
4
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1
answer
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Why is zsh listening on port 22?
I'm SSH'ed into a virtual machine and looking at /proc/<pid>/net/tcp for my zsh shell. I see this line
sl local_address rem_address st tx_queue rx_queue tr tm->when retrnsmt uid ...
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2
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44
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What is the difference between 0.0.0.0:99 and [::]:99?
My ss -lt
shows these lines
LISTEN 0 4096 127.0.0.53%lo:domain 0.0.0.0:* ...
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588
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Program cannot acquire the capabilities it needs (raw sockets)
Note: This is partly a programming question, but my gut feeling is that this has more to do with the Linux' security capabilities framework in general, hence posting here instead of StackOverflow.
I ...
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481
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What does SCM mean in unix sockets context (SCM_RIGHTS etc.)?
From man 7 unix
SCM_RIGHTS
Send or receive a set of open file descriptors from another
process. The data portion contains an integer array of the file
descriptors. The passed file descriptors ...
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995
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Clear socket buffer of CAN adapter
I have a USB/CAN adapter, from lsusb:
OpenMoko, Inc. Geschwister Schneider CAN adapter
it provides a socket interface, from ip addr:
5: can0: <NOARP,UP,LOWER_UP,ECHO> mtu 16 qdisc pfifo_fast ...
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