09-22-2010
Are you actually closing the socket before the program ends?
10 More Discussions You Might Find Interesting
1. IP Networking
:cool:
I want to use 2 tcp applications in SCO 5.05 senerio I am using
VisionFS 3.1 and I need to set it up as a secondary tcp app. I follow the profeditoir and change the tcp port from the primary port (139) to any other number below port 1024 and then restart the VisionFS server it is still... (2 Replies)
Discussion started by: lanman
2 Replies
2. UNIX for Dummies Questions & Answers
If I do a netstat -a I can see all the sockets currently open, is there a way that I can tell which application is holding open these sockets ? (3 Replies)
Discussion started by: murphyboy
3 Replies
3. UNIX for Dummies Questions & Answers
Hello, I have a service running (ODBC) and every now and then it will hang and I will have to stop and restart the service. The problem is when I stop the service, it indeed stops the service, but netstat reports a tcp port still open with the fin_wait_2 status. Then I must close the client... (1 Reply)
Discussion started by: raidzero
1 Replies
4. Programming
Hi all,
I'm writing a socket program which sends a structure from one machine to another. When I run my client first time it runs well, however after the first time I couldn't receive all the data inside the structure (it is like, half of the array is received and the other half is not set). I... (1 Reply)
Discussion started by: SaTYR
1 Replies
5. Programming
Hello. I would like to know how to close an existing tcp socket. I have read some stuff and learned how to create a socket and then close it but have not found anything about how to close an existing tcp socket created by another application. The situation is this: I have an ODBC server running and... (6 Replies)
Discussion started by: raidzero
6 Replies
6. Solaris
Hi,
I use solaris Unix .
I find there is some problem in application and it generate many "close-wait" tcp connect and stay in the server . it is generate by process id 7740
root@XX # netstat -an | grep CLOSE_WAIT | wc -l
285
root@XX # netstat -an | grep CLOSE_WAIT
10.158.35.4.34805 ... (2 Replies)
Discussion started by: abcdef
2 Replies
7. Programming
can someone provide an example, where if the parent process quits for any reason, then the child process will also close? (3 Replies)
Discussion started by: omega666
3 Replies
8. IP Networking
Hello All,
I am very new to socket programming and client server architecture. I have to write a client which will send some data to server and server will display it on its console. I am ready with both client and server but my problem is with packetizing of data --
I have... (1 Reply)
Discussion started by: anand.shah
1 Replies
9. Shell Programming and Scripting
Hi
I want to write a script that will back up one directory if a certain application launches and then backs up another directory if that same application is closed down.
NFI where to start. It seems like cron isn't the tool for this because that is time based. I'm thinking I need... (6 Replies)
Discussion started by: zorrokan
6 Replies
10. UNIX for Advanced & Expert Users
Good morning, I need your help please
After Restarting Aps or connection, these are connections
tcp 0 0 10.80.1.26.57597 10.81.248.79.53008 ESTABLISHED
tcp 0 47 10.80.1.26.57607 10.81.248.79.53008 ESTABLISHED
tcp 0 0 ... (4 Replies)
Discussion started by: alexcol
4 Replies
tcp(4p) tcp(4p)
Name
tcp - Internet Transmission Control Protocol
Syntax
#include <sys/socket.h>
#include <netinet/in.h>
s = socket(AF_INET, SOCK_STREAM, 0);
Description
The TCP protocol provides reliable, flow-controlled, two-way transmission of data. It is a byte-stream protocol used to support the
SOCK_STREAM abstraction. TCP uses the standard Internet address format and, in addition, provides a per-host collection of ``port
addresses''. Thus, each address is composed of an Internet address specifying the host and network, with a specific TCP port on the host
identifying the peer entity.
Sockets utilizing the TCP protocol are either ``active'' or ``passive''. Active sockets initiate connections to passive sockets. By
default TCP sockets are created active; to create a passive socket the system call must be used after binding the socket with the system
call. Only passive sockets can use the call to accept incoming connections. Only active sockets can use the call to initiate connections.
Passive sockets can ``underspecify'' their location to match incoming connection requests from multiple networks. This technique, termed
``wildcard addressing'', allows a single server to provide service to clients on multiple networks. To create a socket that listens on all
networks, the Internet address INADDR_ANY must be bound. The TCP port can still be specified at this time. If the port is not specified,
the system will assign one. Once a connection has been established, the socket's address is fixed by the peer entity's location. The
address assigned the socket is the address associated with the network interface through which packets are being transmitted and received.
Normally, this address corresponds to the peer entity's network.
TCP supports one socket option that is set with and tested with Under most circumstances, TCP sends data when it is presented; when out-
standing data has not yet been acknowledged, it gathers small amounts of output to be sent in a single packet, once an acknowledgement is
received. For a small number of clients, such as window systems that send a stream of mouse events that receive no replies, this packeti-
zation may cause significant delays. Therefore, TCP provides a Boolean option, TCP_NODELAY (from to defeat this algorithm. The option
level for the call is the protocol number for TCP, available from
Diagnostics
A socket operation may fail with one of the following errors returned:
[EISCONN] Try to establish a connection on a socket which already has one.
[ENOBUFS] The system runs out of memory for an internal data structure.
[ETIMEDOUT] A connection was dropped due to excessive retransmissions.
[ECONNRESET] The remote peer forces the connection to be closed.
[ECONNREFUSED] The remote peer actively refuses connection establishment (usually because no process is listening to the port).
[EADDRINUSE] An attempt is made to create a socket with a port that has already been allocated.
[EADDRNOTAVAIL] An attempt is made to create a socket with a network address for which no network interface exists.
See Also
getsockopt(2), socket(2), inet(4f), intro(4n), ip(4p)
tcp(4p)