Get opened TCP sockets

list_tcp_socket

FILE *fp;
char cmd[1024];
char out[1024];
sprintf(cmd, "lsof -p %d 2> /dev/null | grep TCP | awk '{print $9}'", getpid());
fp = popen(cmd, "r");
if (fp == NULL) {
    printf("Failed to run command\n");
    exit(1);
}

while (fgets(out, sizeof(out)-1, fp) != NULL) {
    printf("%s", out);
}

pclose(fp);