I want to create a program exploit that calls testme.c to perform a buffer overflow operation which should call another program myname.c.

The code for the testme.c program:

#include <stdio.h>
#include <string.h>

int main(int argc, char **argv){
    char a[100], b[100], c[100], d[100];
    // Call the exploitable function
    exploitable(argv[1]);
    return(0);
}

int exploitable(char *arg){
    // Make stack space of 10 bytes
    char buffer[10];
    // Copy input to buffer
    strcpy(buffer, arg);
    printf("The buffer says .. [%s/%p].\n", buffer, &buffer);
    return(0);
}

The code for the myname.c program:

#include <stdio.h>
#include <time.h>

int main(){
    printf("Name: SNS\n");
    printf("Location: 41.13957, -104.81815\n");
    time_t t;
    time(&t);
    printf("Date and time: %s\n",ctime(&t));
}

I have disabled address randomization and compiled both programs with -fno-stack-protector. Using gdb I can see that in testme.c, the return address after calling the exploitable function is 0x00000000000011a0:
testmemain

I need this to change to 0x00000000000011a9, which is the address of the main function of the myname.c program:
mynamemain

I know how to overflow the buffer variable in the exploitable function by giving a long enough string input to get a segmentation fault, but I cannot proceed any further than this. I have checked other tutorials in which the next step is to show how to spawn a shell, but I want testme.c to call myname.c through a buffer overflow. I am doing this on a 64-bit Ubuntu virtual machine.