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#include <iostream>
#include <iomanip>
#include <cstdio>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <cstring>
#include <netinet/udp.h>
#include <cstdlib>
#include <arpa/inet.h>
#include <netdb.h>
#include <string.h>
#include <ctype.h>
using namespace std;
int main(int argc, char * argv[])
{
int sock;
unsigned int serverlen;
unsigned int clientlen;
char buffer[256];
int received = 0;
char command[100];
int count=0;
char *comnd1[] = { "/bin/ls", "-l", NULL, NULL, NULL, NULL };
struct sockaddr_in echoserver;
struct sockaddr_in echoclient;
// Create the TCP socket
if ((sock = socket(AF_INET, SOCK_STREAM, 0)) < 0)
{
perror("Failed to create socket");
exit(EXIT_FAILURE);
}
// Construct the server sockaddr_in structure
memset(&echoserver, 0, sizeof(echoserver));
echoserver.sin_family = AF_INET;
echoserver.sin_addr.s_addr = INADDR_ANY;
echoserver.sin_port = htons(atoi(argv[1]));
// Bind the socket
serverlen = sizeof(echoserver);
if (bind(sock, (struct sockaddr *) &echoserver, serverlen) < 0)
{
perror("Failed to bind server socket");
exit(EXIT_FAILURE);
}
// listen: make socket passive and set length of queue
if (listen(sock, 64) < 0)
{
perror("listen failed");
exit(EXIT_FAILURE);
}
// Run until cancelled
while (int newSock=accept(sock, (struct sockaddr *) &echoclient, &clientlen))
{
if ((received = read(newSock, buffer, 256)) < 0)
{
perror("Failed to receive message");
exit(EXIT_FAILURE);
}
if (fork())
{ // parent process
close(sock);
}
else
{
// duplicate socket descriptor into standard output
if (dup2(sock, 1) < 0)
{
perror("socket dup2");
exit(EXIT_FAILURE);
}
// prepare argv array of strings
char *argv[] = { (char*)0, (char*)0, (char*)0, (char*)0, (char*)0,(char*)0, (char*)0 };
// parse command into words
for (char *p = strtok(buffer, " "); p; p = strtok(NULL, " "))
{
argv[count++] = p;
}
write(newSock, argv[1], received);
// run command and its arguments via execvp
if (execvp(argv[0], argv) < 0)
{
perror("exec in child after fork");
exit(EXIT_FAILURE);
}
}
}
}
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