Bind error in local socket

Question

I have to write some code which does the following: client reads input from keyboard and sends the string to the server. Server prints client's IP and the string. Compile time is fine, but when I run the code there's bind error "no such file or directory" I already checked beej's guide and other questions on the forum, but couldn't solve the issue. Any help is appreciated.

EDIT: I made the changes you told me to do except to control the return value of read and write because the program doesn't enter the while loop! also, setsockopt doesn't work.

#include<unistd.h>
#include<string.h>
#include<stdlib.h>
#include<sys/types.h>
#include<sys/socket.h>
#include<stdio.h>
#include<sys/un.h>

int main(void)
{
int fd1,fd2,test,lun,n,enable=1;
socklen_t len;
struct sockaddr_un indirizzo_serv, indirizzo_cl;
char buf[100]={0},temp[100]={0};

fd1=socket(PF_LOCAL,SOCK_STREAM,0); //creo socket locale
if(fd1<0)
    perror("Errore nella creazione del socket\n");
else printf("Socket OK\n");

indirizzo_serv.sun_family=AF_LOCAL;
strcpy(indirizzo_serv.sun_path,"/tmp/socket1000");

//lun=strlen(indirizzo_serv.sun_path)+sizeof(indirizzo_serv.sun_family);

if(setsockopt(fd1,SOL_SOCKET,SO_REUSEADDR,&enable,sizeof(int))<0)
    perror("Errore in setsockopt REUSEADDR\n");

test=bind(fd1,(struct sockaddr*)&indirizzo_serv,sizeof(indirizzo_serv));

if(test==0){
    printf("Bind OK\n");
    test=listen(fd1,2);
    if(test==0){
        printf("listen OK\n");
        len=sizeof(struct sockaddr_un);
        while(1){
            fd2=accept(fd1,(struct sockaddr*)&indirizzo_cl,&len);
            if(fd2<0)
                perror("\nErrore nella accept\n");
            else printf("Accept OK\n");

            write(STDOUT_FILENO,"Client - Inserire la stringa da inviare al server: \n",strlen("Client - Inserire la stringa da inviare al server: \n"));
            read(STDIN_FILENO,buf,sizeof(buf));
            write(fd2,buf,strlen(buf));//write(fd1,buf,strlen(buf));
            read(fd2,buf,strlen(buf));
            sprintf(temp,"Server - IP del client: %s\n",indirizzo_cl.sun_path);
            write(STDOUT_FILENO,temp,strlen(temp));
            memset(buf,0,100);
            memset(temp,0,100);
        }
    }
    else perror("Errore nella listen\n");
   }
   else perror("Errore nella bind\n");

   unlink(indirizzo_serv.sun_path);//close(fd1);
   return 0;
}

`write(fd1,buf,strlen(buf));` -->> `write(fd2,buf,strlen(buf));` — wildplasser, Apr 16 '17 at 15:23

score 0 · Accepted Answer · answered Apr 16 '17 at 15:28

0

The compilation still has issues (test=0 => test==0; int len; => socklen_t len; (wrong signedness)). You should compile with -Wall and sort them out before asking.

Your error is most likely due a missing directory in the path. Substituting a sure-to-exist path such as /tmp/socket1 makes it work on my PC.

answered Apr 16 '17 at 15:28

Petr Skocik

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test=0 was just a typo – rafc Apr 18 '17 at 08:13

score 0 · Answer 2 · answered Apr 16 '17 at 16:06

You are writing to your listen socket, Change :

write(fd1,buf,strlen(buf));

into:

write(fd2,buf,strlen(buf));

Also: instead of ( memset(buf,0,100); ) zeroing your buffers on every loop, you should check the return value you get from read()

and:

if(test=0){

is always false, since it is an assignment. (mabe you want if(test == 0){ ? )

Bind error in local socket

2 Answers2

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