Questions tagged [socket]
is a data communications endpoint for exchanging data between processes executing within the same host operating system.
431 questions
0 votes
0 answers
20 views
Do posix functions like getpeername or getsockname completely rewrite their buffers?
I am new to socket programming & I have realized that most posix functions from libc require that you pass a buffer & a length. While I can understand this helps the functions to understand ...
- 679
2 votes
1 answer
109 views
What is the cost of listening on ports?
If you would open a listening socket on every possible TCP/UDP port (so thousands in total), without actually using them, what would be the cost in terms of performance? Is it merely an administrative ...
- 233
2 votes
1 answer
390 views
TCP checksum offloading on virtio-net paravirtualized interfaces
Consider the topology where 2 QEMU VMs running Linux Ubuntu 16.04 kernel version 4.4.0-210 have both virtio-net interfaces with TAP backends connected to the same (host) Linux bridge and an SSH ...
- 385
0 votes
1 answer
59 views
Getting ancillary data of a packet after recv() call
Is there a way to get struct msghdr or ancillary data of it for the last received packet, i.e. after the recv() call? My guess is that recvmsg() is the only way to populate msghdr, but probably there ...
- 1
2 votes
1 answer
214 views
socat pty,echo=0 terminal option does not work
I'd use socat to redirect the STDIN/STDOUT of the process executing docker run -it ubuntu bash command to a tcp socket in listening on port 32000. root@eve-ng:~# socat -d -d -d EXEC:'docker run -it ...
- 385
1 vote
0 answers
171 views
Using socat to redirect docker attach's STDIN/STDOUT to a TCP socket
I'd like to use socat to redirect the STDIN/STDOUT of the process executing docker attach <container-id> to a listening TCP socket on my Linux system. root@eve-ng:/opt/unetlab# tty /dev/pts/2 ...
- 385
0 votes
0 answers
54 views
Why does Ctrl+C clear the current input line in my Python socket-based Telnet-like shell?
I'm building a simple shell server using raw Python sockets (not using telnetlib). The client connects using PuTTY with the Telnet connection type. The server displays a basic prompt like: [user@...
0 votes
1 answer
96 views
Issue in l2cap test - Bluez
I'm currently testing the bluez tools like l2ping & l2test, So my intention was to interface between two devices through l2cap layer. I have cloned the bluez repository on two raspberry pi devices,...
- 1
0 votes
0 answers
103 views
/dev/log is a socket not a symbolic link
I am trying to understand why one of my system has /dev/log as a socket and other has /dev/log as a symbolic link. [ec2-user@ip-171-31-12-17 log]$ file /dev/log /dev/log: symbolic link to /run/systemd/...
0 votes
1 answer
130 views
Configure mpd to only start a UNIX socket
Running mpd without any bind_to_address in the config starts a working UNIX socket at /run/user/1000/mpd/socket but also starts a network socket at 0.0.0.0:6600 / [::]:6600. I would like to have only ...
- 113
7 votes
2 answers
1k views
ICMP echo traffic doesn't NEED to be operated on a raw socket any more than UDP or TCP traffic does, so why is it done that way?
If you've ever tried writing tools that depend upon ICMP echo requests, you've inevitably run into the same problem as everyone else: you can't do it unless your tool is running as root. When you try ...
1 vote
1 answer
180 views
Ham Radio simulator: live streaming microphone audio between 2 browsers, connected via ubuntu 22
I am trying to simulate a radio with a PTT button. Connected users should be able to live voice chat in the group, one at a time, while holding a button. I have a Ubuntu 22.04 server running, with ...
0 votes
0 answers
163 views
Postfix/Dovecot configuration to gmail as relay
Does any one have a complete configuration of using Dovecot to handle OAuth2 tokens to allow Postfix to send mail to gmail? Most use cases found are either too old or not complete. I have done the ...
1 vote
2 answers
1k views
OpenSSH SSH daemon: IPv4-socket missing on Ubuntu 24.04
I stumbled over the following issue, while debugging ssh connections. I have a Ubuntu 24.04 with openssh-server installed. The corresponding systemd-service is running (now named ssh.service & ssh....
- 11
10 votes
5 answers
1k views
How to check multiple hosts for simple connectivity?
I need a tool that tells me if a connection to a host is open or not -- no data to send or receive, just see if the connection is successful. Today I use telnet. $ telnet myhost myport Trying 192.168....
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