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

int main( int argc, char *argv[] )
{
    char cmdStr[256], *user, hostname[256];

    memset(hostname, 0x00, sizeof(hostname));

    gethostname(hostname, sizeof(hostname));
    user = (char *)getenv("USER");

    if( user == NULL )
    {
	strcpy(user, "unknown");
    }

    while(1)
    {
	printf("%s@%s: ", user, hostname);
	memset(cmdStr, 0x00, sizeof(cmdStr));
	/*
	 * use fgets instead of gets. don't wanna be exploitable!
	 * 
	 * remember that fgets traps everything typed into the command
	 * line, event the carriage return!
	 */
	fgets(cmdStr, sizeof(cmdStr), stdin);

	if( strncmp("quit", cmdStr, 4) == 0 )
	{
	    /*
	     * exit
	     */
	    break;
	}
	else if( strncmp("set", cmdStr, 3) == 0 )
	{
	    /*
	     * set an environment variable
	     */
	    //setenv(parm1, parm2, true);
	    printf("environ var not set\n");
	}
	else
	{
            /*
             * Sure, I'm cheating.  You'd have to be a masochist (sp) to
             * do otherwise.... or your professor requires it.
             */
	    system(cmdStr);
            /*
             * futher thought says one could use execve()/execvp()
             * to handle processes. but you'll want to parse out
             * command line arguments and stuff
             */
	}
    }

    return 0;
}