is a data communications endpoint for exchanging data between processes executing within the same host operating system.

learn more… | top users | synonyms

2
votes
1answer
234 views

Advantages of using named pipes and sockets rather than temporary files

I have two cooperating programs. One program just writes its output to a file and the other one then reads from the file and spits the data out for the front end to work with. I have been reading ...
2
votes
2answers
11k views

ssh: Read from socket failed: Connection reset by peer

When I try to ssh to a remote host, I get the following error messages: root@cloudstack-server-1:~/.ssh# ssh ubuntu@172.17.4.17 -v OpenSSH_5.9p1 Debian-5ubuntu1.1, OpenSSL 1.0.1 14 Mar 2012 ...
2
votes
1answer
571 views

Using a Unix Domain Socket to Control VLC

I am interested in using a UNIX-Domain Socket to control VLC playback. This functionality is outlined in the VideoLan documentation for using oldrc. So what I need to is startup vlc with a command ...
2
votes
1answer
973 views

Espeak showing some warnings and Input output error

I am running espeak on Linux Mint 14. Whenever I try to run it, it shows following warnings ( Not errors as it works correctly ). ALSA lib pcm.c:2217:(snd_pcm_open_noupdate) Unknown PCM ...
2
votes
1answer
180 views

Wrapping socket connections

I'd like to wrap an insecure connection (this one: http://culturedcode.com/things/) with a secure tunnel, a bit like http://en.wikipedia.org/wiki/Stunnel does, just using UNIX tools. What's the best ...
2
votes
1answer
213 views

Connect through different interfaces to the same server (SO_BINDTODEVICE): Destination Host Unreachable

I have 2 interfaces: eth0 and wlan0, each one connected to a different router. Their network specs are these: eth0: ip: 192.168.1.7 Gateway: 192.168.1.1 Submask: 255.255.255.0 wlan0: ...
2
votes
0answers
27 views

Placing OpenSSH control socket in /run

OpenSSH has a feature that allows you to multiplex connections over a controlsocket. It is generally accepted that these control sockets should not reside in a common area, due to the security issues ...
2
votes
3answers
364 views

Nginx leaves old socket

I'm running Nginx 1.6.2 (the nginx-full package from the nginx/stable PPA). I'm using the unmodified configuration /etc/nginx/nginx.conf: user www-data; worker_processes 4; pid /run/nginx.pid; ...
2
votes
0answers
119 views

Emulate console by sending data on one UDP port, and receive text from another

Note: I also posted this question on SuperUser, because I'm not sure where it belongs I'm trying to establish a "console-like" connection with a National Instruments cRIO-FRC. It broadcasts its ...
2
votes
0answers
287 views

X11 bad access at first try but working on successive tries

I use the following setup to forward X11 output from my local machine to the server. I will outline the setup: X11 server and the client are on the same local machine. The X11 server runs on my ...
2
votes
1answer
85 views

Is there a system call to bind a file descriptor directly into another?

A read() & write() loop would probably be as good as what I'm looking for, but nevertheless is anything like that around or is it impossible because of an obstacle I didn't envisage ? I'm curious
2
votes
0answers
56 views

Last data traffic time for a TCP socket

Is it possible, to find out when was the last time there was any traffic on an opened TCP socket? Keepalive and timeout timers are based on this statistic, so I guess it has to be stored somewhere. ...
2
votes
0answers
269 views

Best location and permissions for socket files [duplicate]

I will have a couple of WSGI applications. They will communicate with nginx using sockets. For that purpose I've created the directory /run/wsgi in which I will place all the socket files that are ...
2
votes
0answers
246 views

How do you write test cases for a web server that uses posix sockets? [closed]

I know how to test it experimentally by running the program, but ideally I would like to test each function I write as I write it. Usually I can't test my functions until I write a whole bunch of ...
2
votes
0answers
404 views

Does epoll give available bytes to read or write, and threshold feature?

kqueue gives available bytes to send or receive if file descriptior (such as socket) gets signal. and, kqueue gives threshold feature, for example, it does not signal until sufficient bytes are ...
1
vote
1answer
319 views

How can I allow applications to bind to any address in a subnet assigned to an interface?

I recently got a static IPv6 /56 prefix of my own from Freenet6, and am trying to allow applications to bind arbitrary addresses in the prefix. I modified the tunnel creation script that gogoc uses in ...
1
vote
2answers
937 views

How to “listen” to nginx writes to a file socket

I'm trying to get uwsgi and nginx to play nice. After moving to "file sockets" (hopefully I'm using the right terminology here) from TCP sockets, the only thing I get from uwsgi is a 400 with no ...
1
vote
1answer
58 views

Is it possible to establish a Socket session (between Server and Client) using shell commands ?

From what I read (only the very outline, i do not know C Language) a Socket session is established between a server and a client by calling functions for both of them in a certain order. It starts ...
1
vote
3answers
341 views

nc not waiting for server disconnect on OS X

How to make nc client on OS X Mavericks keep socket open and read data until server disconnects the socket? I want to send data to a server through nc and then use the response. Problem is that nc ...
1
vote
2answers
191 views

How to see the amount of pending data on a unix domain socket?

When I'm logged to a tmux session from two different computers, I'd like to be able to trace the amount of pending data on the sockets of both tmux session. To test this I logged to computer A and to ...
1
vote
1answer
14 views

What setsockopts() 'name' values are used by the running Linux kernel?

I am introducing some new socket commands with nf_register_sockopt(&my_new_socket_options). How can I find, what setsockopt commands are already used (registered?) by the currently running kernel, ...
1
vote
1answer
112 views

ss is replacing netstat, how can I get it to list ports similarly to what I am used to?

I've been trying to modernise my way with Linux by, for one thing, ditching netstat for ss. I looked up my favourite command line flag for netstat in the ss man pages, and was very glad to find that ...
1
vote
1answer
136 views

ip forwarding to remotely connect to a socket listening to localhost only?

I must transfer data from PC1 to PC2 using a specific port, but the socket opened on PC2 only listens to local host. Is there a way to "trick" the socket into accepting the connection from PC1?
1
vote
1answer
6k views

Could not bind socket: Permission denied when trying to start NDOUtils using UNIX socket

I followed these directions to a tee: http://shah-oss.blogspot.com/2010/12/ndoutils-installation-on-centos-for.html Everything was going well until I actually tried to run this command (there is a ...
1
vote
1answer
1k views

Default value for SO_RCVTIMEO option on Solaris

Is there any way to find out what is the default value set for option SO_RCVTIMEO on Solaris 10? If there is a way to find out how would one go about changing it? P.S. I am aware of ability of ...
1
vote
0answers
40 views

How to know file name of sockets or pipes in /proc/[pid]/fd

In Android, #ls -l 15843/fd gives following output, lrwx------ u0_a179 u0_a179 2015-05-28 11:58 90 -> socket:[193728] lrwx------ u0_a179 u0_a179 2015-05-28 11:58 91 -> ...
1
vote
0answers
53 views

What does an inode for a socket contain?

I read somewhere that the inode for a TCP socket would contain the buffer space. Is that true, and if so, does it mean that the inode contains a memory address for the buffer space used by the ...
1
vote
1answer
49 views

how do applications communicate via sockets

On my computer audio works sometimes and sometimes not. I want to troubleshoot this. First I verified I am using pulseaudio. I did this by strace'ing the pulseaudio process: [pid 2289] send(28, ...
1
vote
1answer
1k views

Installing vsftpd - 500 OOPS: could not bind listening IPv4 socket?

I have to set up a FTP server on my machine. I have installed vsftpd using the command: sudo apt-get install vsftpd I then edited the configuration file vsftpd.conf in the location /etc. The file ...
1
vote
0answers
111 views

/private/var socket not created with postfix/dovecot sasl

I'm currently running into a problem I have with my email server. I try to setup Postfix and Dovecot with SASL authentication but I get the following error when I connect with telnet (port 25) to the ...
1
vote
0answers
43 views

Which Privileges Should Assign For Create Raw Sockets

I want to run an ICMP command to ping an IP Adress at Java: InetAddress.getByAddress("XXX.XXX.XXX.XXX".getBytes()).isReachable(1000); However there is a security restriction that: Normal users are ...
1
vote
1answer
19 views

How to apply a parameter to packet so TC can prioritize\classify it

I want to add a parameter to the packet so that I can later let TC (HTB in specific) prioritize my packet (based on filtering that parameter). I thought about filtering by socket but as I understand ...
1
vote
3answers
132 views

Server running on guest Linux VM will not accept connections from Windows host

I have a simple echo server program running on CentOS 7. If I run both the client and the server in the VM, I can connect to the server. I'm using VirtualBox with the "bridged" network configuration. ...
1
vote
0answers
79 views

Why was n't kqueue socket polling mechanism not implemented in Linux?

Linux has epoll for socket polling mechanism. kqueue seems to be better than epoll. Why did linux went with epoll rather than kqueue? I read about libkqueue. But that is implemented in user space and ...
1
vote
0answers
329 views

Which socket is gnome-shell reading from continuously?

strace shows that the GNOME shell is continuously trying to read from a socket, which is often not available (or doesn't contain any data to read from): strace -p gnome-shell-pid -e trace=recvfrom ...
1
vote
1answer
156 views

Communication to device is lost when network starts on boot up?

I have an application that opens a socket on port 4444 to a device (/dev/linkToDevice). The "linkToDevice" is a link to ttyUSB0. The application is a c++ program of which is now a daemon and runs at ...
1
vote
0answers
1k views

Symbolic link to a socket

From a security point of view, is it safe to create a symbolic link to a socket file? The following bits of context refer to the deployment of a web application on a shared hosting service. $ ls -al ...
1
vote
1answer
828 views

Netstat shows programs running on different ports then they should

I have some code I'm testing. Program A listens on a predefined socket for program B to connect to and for my testing I'm running 32 instances of the programs A and B. I've written my script to tell ...
1
vote
1answer
1k views

Where to locate “sockets”

I am new to this, so sorry if its obvious. I am running a Debian server and installing the likes of UWSGI, NGinx etc on there. The configurations keep talking about pointing to "sockets". In the ...
1
vote
1answer
418 views

How to limit all tcp traffic to the network interface the session was initiated on?

I have an embedded linux system with two network interfaces (lan0, wlan0) that are configured to the same subnet. A server on this system accepts tcp connections on both interfaces. How I can assure ...
0
votes
1answer
1k views

How to connect to port immedeately, avoiding socket_bind(): unable to bind address?

When running a code that is supposed to read from a TCP/IP port I often get the following message (depending exactly what language have been used): socket_bind(): unable to bind address I know that ...
0
votes
1answer
26 views

Path to unix socket

I'm using p0f to fingerprint network OSs from traffic captures. p0f has a feature allowing it to be set up as a daemon and listen in the background for a connection from a p0f-client (ie: ...
0
votes
1answer
322 views

Opening a socket in Kali Linux using bash scripts

I know how to open a TCP or UDP socket in Ubuntu, with the following command : exec 3<>/dev/tcp/google.com/80 for example: we can open a TCP socket on port 80, but in Kali Linux there's no ...
0
votes
2answers
153 views

Runs perfectly through the command line, will not work through systemd ExecStart

I've installed Butterfly http terminal server, written in python, on my Arch machine. I'm new to systemd, but I'm having an issue with one of the command line parameters. /usr/bin/butterfly.server.py ...
0
votes
2answers
113 views

Why flipping is done on data from Big endian before storing in LE?

Simple but confusing question for a beginner. Suppose A is a BE machine and is sending 0x44332211 sending data to B which is LE. By default A will be using htonl of 0x44332211 which is nothing but ...
0
votes
1answer
812 views

pcap and raw socket [closed]

I want to develop an application (module or user-level if possible) to create a raw socket in RHEL stealing all level-2 packets directly from kernel (without being routed or handled by other open ...
0
votes
1answer
32 views

Forwarding a udp socket connection to a range of ip addresses

I have a program which is a udp socket client. I can determine an IP adress to which this program should send. Unfortunately, I configured the computer as Access Point and don't know the address of ...
0
votes
2answers
1k views

Force getaddrinfo to use IPv4

The man page says: The getaddrinfo(3) function is not limited to creating IPv4 socket address structures; IPv6 socket address structures can be created if IPv6 support is available. These ...
0
votes
1answer
36 views

Finding out the number of dropped packets in raw sockets

I am developing a program that sniffs network packets using a raw socket (AF_PACKET, SOCK_RAW) and processes them in some way. I am not sure whether my program runs fast enough and succeeds to ...
0
votes
1answer
45 views

Who opened a file descriptor? (socket)

I am using strace to track a program. In this line: recvfrom(7, "\0\260R\0\0\1\364\6\215\r\257\330\210\341\0\270\240\0\260R\0\0\0\0\0\0\0\0\0\0\0\0"..., 3000, 0, {sa_family=AF_PACKET, proto=0x88e1, ...