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

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1answer
922 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
176 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
105 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
9 views

Scripted write-then-read from Unix domain socket using socat

I have a simple server listening on a Unix domain socket (on a CentOS box in case that's important). When I send the command "DATE" to the socket it writes back a welcome message and then "APRIL 15 ...
2
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0answers
22 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
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0answers
109 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
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0answers
183 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
75 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
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0answers
48 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
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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
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0answers
225 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
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0answers
379 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
247 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
781 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
38 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
261 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
170 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
13 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
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1answer
67 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
116 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
5k 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
1answer
35 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, ...
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0answers
22 views

Python embedded in bash not working [migrated]

I want to embed a small python script inside a bash script so that I can send a json object to a socket. I have tried the following code: python -c "$(cat << 'EOF' import socket import json ...
1
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1answer
283 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 ...
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0answers
79 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 ...
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0answers
33 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 ...
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0answers
56 views

Unix domain Sockets - Size limitation? [closed]

I have the following scenario I created a socket with socat - unix-listen:/tmp/socket.sock then I wrote a very long string (abt 40k) with nc -U /tmp/socket.sock I seted the following parameters ...
1
vote
1answer
226 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; ...
1
vote
1answer
17 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
107 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. ...
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0answers
67 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
293 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
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0answers
147 views

Solaris 10 on x86: local sockets (unix domain sockets) very very slow? [closed]

I'm writing an application both on Linux and Solaris 10. It uses local sockets for some internal communications. On Linux an open, exchange one short message & close cycle takes about 10us elapsed ...
1
vote
1answer
153 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
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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
780 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
399 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
241 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
90 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
104 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
755 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
2answers
961 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
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0answers
50 views

Switching from LPD to SOCKET protocol in CUPS?

I have a USB+LAN printer that was USB-connected to a Windows computer and shared via LPD. In CUPS this was configured to be a raw printer. The jobs where processed correctly. I then simply put the ...
0
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0answers
68 views

linux + what are the messages bad tty under /var/log/messages file

under /var/log/messages I see the following messages "bad tty" what the meaning of these messages? second is it caused because some application that called - owstd ? as we can see from the log? ...
0
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0answers
42 views

how to fix a port no statically for client request on client side?

I have an assignment to implement: unicast multicast broadcast in Java socket programming. While implementing the multicast part I decided to do it on my own system itself, so for the purpose of ...
0
votes
0answers
103 views

Stopping syslogd also closes /dev/log UNIX domain socket

I am working on a project and from some testing I found out that stopping syslogd daemon also closes /dev/log socket. Is there some other way so that even if syslogd is down, /dev/log socket still ...
0
votes
1answer
140 views

Archlinux ARM Apache server fails to start

I am currently setting up an Apache web server on my Pi running on Archlinux ARM. After installing and making the first small configurations I have tested it and it works. Then I stop the server and ...