C Source Code

The blue code below is all that's needed to run the show. It is written in ANSI C and should compile, and run, on any POSIX compliant operating system (which includes Windows NT and derivatives).

#include <stdio.h> #include <stdlib.h>
const char * env_var = "SSH_CONNECTION";
int main (int argc, char * argv[]) { char * path = getenv(env_var); printf("%c[%d;%d;%dm", 0x1B, 1, 31, 40); // color output red
if (path == NULL) { printf("This is NOT an SSH session.\n"); fflush(stdout); #ifdef FIREFOX printf("Automatically launching Mozilla Firefox..."); system("add webbrowsers && firefox &"); #endif printf("%c[%d;%d;%dm", 0x1B, 0, 37, 40); // reset colors return EXIT_FAILURE; }
char * ip_address = calloc (sizeof(char), 16); char * path_p = path; char * ip_address_p = ip_address; while ( * path_p != ' ' && * path_p != '\0') { * ip_address_p = * path_p; ip_address_p++; path_p++; }
printf("You are remotely logged in from %s.\n", ip_address); fflush(stdout); free(ip_address); printf("%c[%d;%d;%dm", 0x1B, 0, 37, 40); // reset colors return EXIT_SUCCESS; }

This program tries to open the shells $SSH_CONNECTION environment variable. If there is no such variable, we can safely assume that this session is not being conducted over SSH. I wrote this program to automatically launch Firefox, but to do so, the code must be compiled with -DFIREFOX.

The return values were structured to make shell scripting with this program possible.