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/* A simple server to attach to
*/
#include <sys/types.h>
#include <stdio.h>
#include <errno.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <netdb.h>
char *name;
int sock_fd;
int connect_fd;
void Socket(short);
main(argc,argv)
int argc;
char *argv[];
{
struct sockaddr_in addr;
char buff[1024];
int len;
int addrlen;
name=argv[0];
if (argc!=2)
{
fprintf(stderr,"%s: usage %s port\n",name,name);
exit(1);
}
Socket((short)atoi(argv[1]));
printf("%s: socket bound\n",name);
while(1)
{
printf("%s: accepting\n",name);
if ((connect_fd=accept(sock_fd,NULL,0))==-1)
{
perror(name);
exit(1);
}
addrlen=sizeof(addr);
if (getsockname(connect_fd,&addr,&addrlen)!=0)
perror(name);
printf("%s: connection ON port %d\n",name,ntohs(addr.sin_port));
addrlen=sizeof(addr);
if (getpeername(connect_fd,&addr,&addrlen)!=0)
perror(name);
printf("%s: connection FROM port %d\n",name,ntohs(addr.sin_port));
while((len=read(connect_fd,buff,1024))>0)
{
buff[len]=0;
printf("%s: recieved '%s'\n",name,buff);
write(connect_fd,buff,len);
}
perror(name);
close(connect_fd);
}
return(0);
}
void Socket(short p)
{
struct sockaddr_in addr;
if ((sock_fd=socket(AF_INET,SOCK_STREAM,0))==-1)
{
perror(name);
exit(1);
}
/* Bind port to address
*/
addr.sin_family=AF_INET;
addr.sin_addr.s_addr=INADDR_ANY;
addr.sin_port=htons(p);
if (bind(sock_fd,&addr,sizeof(addr))==-1)
{
perror(name);
exit(1);
}
if (listen(sock_fd,5)==-1)
{
perror(name);
exit(1);
}
}
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