Question

Hello ever one I have made a main function and two files one header and one c file

main.c

#include "sev.h"

int main(int argc, char *argv[])
{
     int sockfd, newsockfd, port_no = 1234, index=0;
     struct sockaddr_in serv_addr, cli_addr;

    fill_server_address(&serv_addr, port_no);

}

sev.c

#include "sev.h"

    void 
    fill_server_address(struct sockaddr_in *serv_addr, int port_no)
    {
        serv_addr->sin_family = AF_INET;
        serv_addr->sin_port = htons(port-no);
        serv_addr->sin_addr.s_addr = INADDR_ANY;

    }

sev.h

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

void fill_server_address(struct sockaddr_in *serv_addr, int port_no);

but in main I am still getting an error

/tmp/cca5VCjZ.o: In function main': server-main.c:(.text+0x106):
undefined reference tofill_server_address’ collect2: ld returned 1
exit status

Although I have define the function and included it but still why do I am getting this error Can any one please help me to fix it

thanks

Answer 1

Including the header is not enough. You also need to compile sev.c and link it into the executable:

gcc main.c sev.c