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/*
Reader/writer to TCP/IP socket
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <netdb.h>
static const char *name;
static const char *GetLine(void)
{
static char buff[1024];
int l;
if (feof(stdin))
{
return(NULL);
}
printf("> ");
if (!fgets(buff, sizeof buff, stdin))
{
return(NULL);
}
l=strlen(buff);
if (l > 0 && buff[l-1]=='\n')
{
buff[l-1]=0;
}
if (strlen(buff))
{
return buff;
}
else
{
return GetLine();
}
}
static int Connect(const char *n, const char *p)
{
struct addrinfo *addr, *addr_p;
struct addrinfo hints = {0};
int status;
int sock = -1;
hints.ai_family = PF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
status = getaddrinfo(n, p, &hints, &addr);
if (status)
{
fprintf(stderr, "%s: %s\n", name, gai_strerror(status));
exit(EXIT_FAILURE);
}
for(addr_p = addr; addr_p && sock == -1; addr_p = addr_p->ai_next)
{
sock = socket(addr_p->ai_family,
addr_p->ai_socktype,
addr_p->ai_protocol);
if (sock != -1)
{
if (connect(sock, addr_p->ai_addr, addr_p->ai_addrlen) == -1)
{
close(sock);
sock = -1;
}
}
}
if (sock == -1)
{
fprintf(stderr, "%s: Failed to connect to %s:%s\n", name, n, p);
exit(EXIT_FAILURE);
}
return sock;
}
int main(int argc, char *argv[])
{
struct sockaddr_in addr;
int addrlen;
const char *p;
char buff[1024];
int len;
int sock;
int no_read;
int no_write;
name=argv[0];
if (argc<3)
{
fprintf(stderr,"%s: usage %s host port [nowrite|noread]\n",name,name);
exit(EXIT_FAILURE);
}
if (argc > 3)
{
no_read = strcmp(argv[3], "noread") == 0;
no_write = strcmp(argv[3], "nowrite") == 0;
}
else
{
no_read = 0;
no_write = 0;
}
sock = Connect(argv[1],argv[2]);
/* Test to see how to get the connected local port number
*/
addrlen=sizeof(addr);
if (getsockname(sock,(void*)&addr,&addrlen)!=0)
{
perror(name);
}
printf("%s: bound through port %d\n",name,ntohs(addr.sin_port));
while(no_write || (p=GetLine()))
{
if (!no_write && (write(sock,p,strlen(p))==-1))
{
perror(name);
close(sock);
exit(EXIT_FAILURE);
}
if (!no_read)
{
if ((len=read(sock,buff,1024))<=0)
{
perror(name);
close(sock);
exit(EXIT_FAILURE);
}
buff[len]=0;
printf("%s\n",buff);
}
}
close(sock);
printf("\n");
return EXIT_SUCCESS;
}
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