Suppose i am writing a C program which is going to use Socket calls. I want to use a Unix port for my Socket.
How can i determine a port which is not already in use? (1 Reply)
Hello,
I actually try to make client-server program.
I'm using SCO OpenServer Release 5.0.0 and when I try to compile my code (by TELNET) I've got this error :
I'm just using this simple code :
and I get the same error if I use :
If someone can help me,
Thanks (2 Replies)
Can anyone plz me. I need a sample code for the following description.
Its urgent.
It is C/Socket program with the following descriptions:
NAME
coreadServer - Concurrent Readers Server.
coreadClient - Concurrent Readers Client.
SYNOPSIS
coreadServer <OutputFile>
coreadClient <n>... (1 Reply)
i m using sockets for setting up a connection between a server and a client.
When the clients gets connected to the server, its ip is conveyed to the server through one of the predefined structures in c library...
i save this ip address in an array....1st client's ip address goes to the zeroth... (1 Reply)
Hi,
I am trying to connect to more than 60 servers to perform some actions remotely. for this I am using ssh2. But its taking lot of time.
Though i am running the command in background, still its taking long time to execute..
Any one let me know can we use sockets instead of ssh2 for... (3 Replies)
hi guys i got this code trying to make connection between the server and multi clients but when i do ./server i got message server waiting then when i run ./client it says client 1 nosuch file i dont know whats that should i use any argument plz help how to compile and run and whats the expected... (1 Reply)
in socket programming how can i : Create for example 3 blank files, namely: server, client, network
•Server: act as servers/provider, will receive all requests from different client
•Client: requesters
•Network: middle-layer of communication between server & client
any tips or... (6 Replies)
i'm doing a simple program in socket programming on c i have server that can handle 2clients in a single machine i'm running ubuntu linux so i got it work but the probelm when clients send a message the server will echo it but i cant distinguish which client send the message client 1 or client... (7 Replies)
Hi All
I am getting an error when using the below code
Receiver
use IO::Socket;
$sock = new IO::Socket::INET (LocalHost => 'goldengate',
LocalPort => 1200,
Proto => 'tcp',
Listen => 5,
Reuse => 1
);
die "Socket could not be created. Reason: $!" unless $sock;
while ($new_sock =... (5 Replies)
Discussion started by: parthmittal2007
5 Replies
LEARN ABOUT V7
sockatmark
SOCKATMARK(3) Linux Programmer's Manual SOCKATMARK(3)NAME
sockatmark - determine whether socket is at out-of-band mark
SYNOPSIS
#include <sys/socket.h>
int sockatmark(int sockfd);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
sockatmark(): _POSIX_C_SOURCE >= 200112L
DESCRIPTION
sockatmark() returns a value indicating whether or not the socket referred to by the file descriptor sockfd is at the out-of-band mark. If
the socket is at the mark, then 1 is returned; if the socket is not at the mark, 0 is returned. This function does not remove the out-of-
band mark.
RETURN VALUE
A successful call to sockatmark() returns 1 if the socket is at the out-of-band mark, or 0 if it is not. On error, -1 is returned and
errno is set to indicate the error.
ERRORS
EBADF sockfd is not a valid file descriptor.
EINVAL sockfd is not a file descriptor to which sockatmark() can be applied.
VERSIONS
sockatmark() was added to glibc in version 2.2.4.
ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7).
+-------------+---------------+---------+
|Interface | Attribute | Value |
+-------------+---------------+---------+
|sockatmark() | Thread safety | MT-Safe |
+-------------+---------------+---------+
CONFORMING TO
POSIX.1-2001, POSIX.1-2008.
NOTES
If sockatmark() returns 1, then the out-of-band data can be read using the MSG_OOB flag of recv(2).
Out-of-band data is supported only on some stream socket protocols.
sockatmark() can safely be called from a handler for the SIGURG signal.
sockatmark() is implemented using the SIOCATMARK ioctl(2) operation.
BUGS
Prior to glibc 2.4, sockatmark() did not work.
EXAMPLE
The following code can be used after receipt of a SIGURG signal to read (and discard) all data up to the mark, and then read the byte of
data at the mark:
char buf[BUF_LEN];
char oobdata;
int atmark, s;
for (;;) {
atmark = sockatmark(sockfd);
if (atmark == -1) {
perror("sockatmark");
break;
}
if (atmark)
break;
s = read(sockfd, buf, BUF_LEN);
if (s == -1)
perror("read");
if (s <= 0)
break;
}
if (atmark == 1) {
if (recv(sockfd, &oobdata, 1, MSG_OOB) == -1) {
perror("recv");
...
}
}
SEE ALSO fcntl(2), recv(2), send(2), tcp(7)COLOPHON
This page is part of release 4.15 of the Linux man-pages project. A description of the project, information about reporting bugs, and the
latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.
Linux 2017-09-15 SOCKATMARK(3)