cliente.c

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <pthread.h>
#include <string.h>

#define SERVER_PORT     4012
#define SERVER_ADDRESS  "127.0.0.1"
#define MAXLINE         512

void* recibir(void* p);
void* enviar(void* p);
int flag=0;

int main()
{
        struct sockaddr_in addr;
        int sd,status;
        pthread_t hilos[2];

        addr.sin_family = AF_INET;
        addr.sin_addr.s_addr = inet_addr(SERVER_ADDRESS);
        addr.sin_port = htons(SERVER_PORT);

        if((sd = socket (AF_INET, SOCK_STREAM, 0)) == -1)
        {
                printf("Error al crear el socket\n");
                exit(0);
        }
        if(connect(sd, (struct sockaddr *)&addr, sizeof(addr)) == -1)
        {
                printf("Error al conectar\n");
                exit(0);
        }
        else
        {
                if ( (status = pthread_create(&hilos[0],NULL,recibir,(void*)&sd)) )                             //La función pthread_create() devuelve 0 si todo ha ido bien. Un valor distinto de 0 si ha habido algún problema y no se ha creado el thread.
                {
                        printf("Error al crear hilo para recibir\n");
                        close(sd);
                        exit(0);
                }
               /*
                if ( (status = pthread_create(&hilos[1],NULL,enviar,(void*)&sd)) )
                {
                        printf("Error al crear hilo para enviar\n");
                        close(sd);
                        exit(0);
                }*/
                pthread_join(hilos[0],NULL);
                //pthread_join(hilos[1],NULL);
        }
        return 1;
}

void* recibir(void* p)
{
        int* id;
        char buffer[MAXLINE];
        id = (int*) p;
        send(*id,"me conecte",MAXLINE,0);
        while(1)
        {
                recv(*id,buffer,MAXLINE,0);

                        printf("\n%s\n",buffer);
                        memset(buffer,'\0',sizeof(buffer));


                        printf("\nTexto: ");
                        gets(buffer);
                        send(*id,buffer,MAXLINE,0);
                        memset(buffer,'\0',sizeof(buffer));

        }
}

void* enviar(void* p)
{
        int* id;
        char buffer2[MAXLINE];
        id = (int*) p;
        while(1)
        {
                printf("\nTexto: ");
                gets(buffer2);
                send(*id,buffer2,MAXLINE,0);
                 memset(buffer2,'\0',sizeof(buffer2));
        }
}