A communication end-point for networking, for CPUs please use [processor-socket]

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58
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13answers
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Manually closing a port from commandline

I want to close an open port which is in listening mode between my client and server application. Is there any manual command line option in Linux to close a port ?? NOTE: I came to know that "only ...
50
votes
2answers
5k views

Why was port 80 chosen as the default HTTP port and 443 as the default HTTPS port?

Why was port 80 chosen as the default HTTP port and 443 as the default HTTPS port? Is there a reason or was it is just defined that way?
26
votes
3answers
19k views

Can I monitor a local unix domain socket like tcpdump?

I'd like to monitor responses on a unix socket without disturbing the original connections and pipe them to a script for processing. I know how to do this with tcpdump for tcp connections but I ...
19
votes
2answers
8k views

Can cURL send requests to sockets?

I can find nothing about this on Google or the cURL man pages. I have a HTTP server running at /var/run/my-server.sock, and I want to test it by sending a simple request using cURL. Can this be done ...
18
votes
3answers
20k views

linux named sockets howto

I know that there are named sockets & named pipes (fifo) in linux. In ls -l, they would look as below:(I have changed the filenames, for demonstration.) prw-r--r-- 1 root root 0 Nov 8 16:31 ...
14
votes
3answers
12k views

Allow non-root process to bind to port 80 and 443?

Is it possible to tune a kernel parameter to allow a userland program to bind to port 80 and 443? The reason I ask is I think its foolish to allow a privileged process to open a socket and listen. ...
12
votes
1answer
1k views

Determining what process has bound a port (without listening) on Windows

If I want to find out what process is listening on what socket, I can use netstat/TCPview and will immediately see it. However, it is possible to bind to an address without listening. If this is done, ...
11
votes
3answers
13k views

Difference between localhost and the ip address

If bind a socket in Python to localhost,8200 this is accessible via http://localhost:8200/. but not http://x.x.x.x:8200/ If bind a socket in Python to x.x.x.x,8200, machinename,8200 this is ...
10
votes
3answers
2k views

Does Windows take care of closing sockets when processes exit?

I've read up this question about Linux, Can a port be bound when the process has terminated? Linux appears to clean up after processes exiting, and leaving open sockets. I was wondering if there's any ...
9
votes
3answers
7k views

How to determine the socket connection up time on Linux

I can verify that the connection is up: $ netstat -tn | grep "192.168.2.110" tcp 0 0 192.168.2.100:10444 192.168.2.110:52639 ESTABLISHED is there a way to check how long this tcp port ...
8
votes
1answer
18k views

What is the simplest way to test a plain socket server

I have a server which listens on a socket for incoming connections and outputs a welcome text ("Hello world"). What is the simplest way to test this with plain tools from the operating system (here OS ...
8
votes
4answers
8k views

sshfs mounting linux directory from mac stopped working

Until this morning, I'd been using sshfs quite nicely to mount a directory from a linux machine in my office. Today, it stopped. Here's my sshfs command: sshfs -osshfs_sync,volname=linux-builder3 ...
6
votes
1answer
14k views

Force socket close

Is it possible to close an established socket connection in Windows "manually" (e.g. using a command prompt tool)? I have several open sockets connected to a listening server, I can see them using ...
6
votes
1answer
2k views

Does Mac OS X throttle the RATE of socket creation?

This may seem programming related, but this is an OS question. I'm writing a small high performance daemon that takes thousands of connections per second. It's working fine on Linux (specifically ...
6
votes
1answer
1k views

Tell GNU screen where to save the sessions?

My GNU screen stores its sessions in the /tmp directory. That means that after a reboot, all sessions are lost: $ screen -list No Sockets found in /tmp/uscreens/S-dehmann. How can I tell it to ...
5
votes
1answer
603 views

Does TCP/UDP send file sequentially or randomnly?

Does TCP/UDP protocol always send or receive file packets sequentially? Would it possible to make a choice which data packets will be sent first using sockets API?
5
votes
2answers
379 views

Linux localhost sockets painfully slower than on Mac

This question is based on this thread over at OpenOffice. I'm using Python and the Office UNO bridge to analyze documents. For the most part I run on my Mac and spin up an office instance to listen ...
5
votes
1answer
3k views

Is sharing a tmux sockets between hosts possible?

I'm wondering if it's possible to share a tmux server socket between different hosts. For example, I have a virtual machine (guest) running inside my host, and I'm running a tmux session in the guest, ...
5
votes
1answer
1k views

Bridging two sockets

I wondered if it is possible to bridge two incoming tcp sockets. For example: Client A -----> Server <----- Client B The the server sends it's magic to both clients and then they connect ...
4
votes
1answer
1k views

How does SSH tunneling work at low level?

I am interested in the exact mechanism that occurs when an SSH tunnel is stablished. Supposing we have 3 computers: LOCAL host, INTERMEDIATE host, and REMOTE host, with this topology: Localhost --- ...
3
votes
5answers
7k views

Will socket 1155 cpu work in 775 mobo

will INTEL Celeron G440 BOX (s. 1155) work in ASROCK G31M-S R2.0 (s. 775) motherboard? I belive I heard that AM3 cpu can work in AM2 mobo is it the same case with intel.
3
votes
4answers
95 views

TCP/IP on the transport level

I'm trying to understand what happens when I send a packet using a socket on the transport level. Do all packets which leave my computer go first to a geographical location designated by my ISP? Then ...
3
votes
1answer
2k views

Remote listening of UNIX sockets

I'd like to be able to remotely listen to UNIX sockets in order to make programs such as dtach, which only support listening to UNIX sockets, work remotely. I've read about socat and how it's able to ...
3
votes
2answers
125 views

Is it bad practice to listen on 0.0.0.0? Why?

Say I want to deploy a software that acts as a server and I want to avoid scenarios where interfaces are replaced, IP addresses are changed, etc. The nature of the environment in which this software ...
3
votes
1answer
868 views

Given that tar ignored my 2 sockets, how do I backup and then restore my login folder?

I did a network backup of my login area in preparation for reformatting the volume in which it resides to make it bootable on my old Power Mac G5 running the very latest release of Leopard. Though ...
3
votes
1answer
230 views

No-socket alternative to tmux or screen

My university gives each student a directory on their AFS which is accessible via SSH. There is a (light) CLI-driven piece of software that I would like to run continuously from the university. I ...
3
votes
2answers
1k views

Access machine in a subnetwork after a router

Is it possible to access a machine in a sub network? This is the situation: Main-router + sub-router - machine (2) - machine - machine - ... - machine (1) - machine - machine - ... ...
3
votes
1answer
908 views

How do I run mysqld as a regular non-daemon program?

I'd like to run a local copy of mysql, to keep software development environments isolated. However, I can't seem to get the mysqld server to start up. I've created a database directory with ...
3
votes
3answers
165 views

Distinct Proxying for any TCP-related Protocol

I'm not sure what to call it (proxy/redirection/relay), and I am hoping some software or solution possibly exists for linux. My intention is to be able to listen on a single public facing ip:port ...
3
votes
1answer
165 views

What happens when I terminate a process and the socket send buffer is not empty?

In Windows (and probably in other operating systems), if a process has a TCP connection with another process on another machine, and then I terminate the process, an RST packet will be sent to the ...
3
votes
1answer
77 views

Is it necessary for an RST packet to have an acknowledgement number?

I am studying about TCP reset attack. I know that some RST packets have an acknowledgement number (with the ACK bit set), and some RST packets do not have an acknowledgement number (the ...
3
votes
2answers
872 views

Data retransmission and WSAECONNABORTED (10053) socket error

Say I have two sockets that are connected to each other (Socket A and Socket B). If the computer that have Socket B is unplugged from power, then if Socket A tries to send some data to Socket B, the ...
3
votes
1answer
2k views

SYN-ACK not received

On a standard TCP connection between server and client, I have this issue: the SYN-ACK is not received from the client, while it is sent from the server. I could see this on Wireshark from both server ...
3
votes
1answer
14k views

socket.error: [Errno 10013] Port forbidden access permissions

When trying to use a Python script I get this error: socket.error: [Errno 10013] An attempt was made to access a socket in a way forbidden by its access permissions I put the post on ...
3
votes
2answers
133 views

Are FIN packets guaranteed to arrive?

In the 4-way handshake, we have the following: FIN -------> <------- ACK <---x--- FIN (what if this packet is lost?) ACK -------> What happens if the third packet is lost, will it be ...
2
votes
2answers
2k views

Can we add more RAM sockets on a motherboard?

If a motherboard has only 4 RAM sockets, then can we add more up to 5 or 6 sockets?
2
votes
2answers
994 views

Can I avoid the ten connection limit of IIS by transferring through sockets?

Can I avoid being limited by IIS's ten-connection ceiling if I transfer files through sockets? I'm using Windows XP.
2
votes
2answers
7k views

TCP: Maximum number of connections (client and server)

In the description of TCP in the Wikipedia, it is stated that The number of sessions in the server side is limited only by memory and can grow as new connections arrive, but the client must ...
2
votes
2answers
5k views

Nginx can't connect to uWSGI socket with correct permissions

I'm trying to connect Nginx to uWSGI so I can run an application written in Ruby (where I am not able to use passenger). This is my virtual host configuration: server { listen ...
2
votes
1answer
6k views

What do Intel's socket package specifications mean in detail?

What is the difference between FCPGA988 PGA988 rPGA rPGA988B BGA1224 FCBGA1224 Do some mean that the BGA is soldered to the board and cannot be removed? BGA is soldered versions only, right? ...
2
votes
1answer
2k views

Dovecot.conf assistance since upgrade

I've been following a guide on this site: http://oskarhane.com/setup-your-own-mail-hosting-with-linux-postfix-dovecot-and-mysql/ To install postfix with dovecot and mysql on a Linux server. All ...
2
votes
1answer
674 views

inetd analog for Windows

Need a better analog of inetd daemon for Windows. Currently using http://sourceforge.net/projects/winetd/, but it's outdated with bugs present. Please recommend any better solutions for running your ...
2
votes
1answer
885 views

Disconnect a Program from its Socket or Port in Windows 7

I am working on a hack for internal purposes whereby I want to disconnect a program from it's socket without killing the process. For example, program A (running xxx.exe) is running on port 50000 and ...
2
votes
1answer
562 views

estimating size of reply HTTP headers

I am trying to download a file via a basic socket connection, using a HTTP GET request. So, I have to specify how many bytes of data coming in I have to read from the socket. However, I am having ...
2
votes
1answer
64 views

How to list socket options of running processes?

Is there a convenient way (e.g. a readily-available command or a program that I can write using standard system calls) to list socket options (e.g. TCP_NODELAY) of an open TCP socket of some running ...
2
votes
0answers
38 views

How to monitor the unix socket statistics in OSX per-seconds

I can monitor a net-device in the OSX, like below $ netstat -I eth0 -b 1 1000 input (Total) output packets errs bytes packets errs bytes colls ...
2
votes
0answers
107 views

netstat -o timer value “probe”

A bit of background on the scenario. I have a distributed application running on RH6.5 that uses JMS (OpenMQ 4.5.2) to send messages between hosts. One host (Host A) receives information from network ...
2
votes
1answer
555 views

Simulating a network issue for a specific application

This is somehow a developer question, but as it is more related to operating systems and network connections, I will post it here and not on Stack Overflow. I'm trying to simulate a situation when a ...
2
votes
1answer
1k views

UDP Hole Punching impossible with non-well-behaved NATs?

Normally a NAT will keep the public end point of a local end point the same for all packets that are coming from it, thus making UDP hole punching easily possible. However, some NATs will map the ...
2
votes
1answer
275 views

How does the Inetutils telnet utility determine if a connection is still alive?

I've started using sockets in programming with Java (I have experience with Python), and while testing a server that I'd written with the telnet command, I noticed that the utility responds ...