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Overview: This application has 3 programs that ask the user to guess 4 yes/no (or 0/1) questions. When the user guesses one bit correctly, they

Overview: This application has 3 programs that ask the user to guess 4 yes/no (or 0/1) questions. When the user guesses one bit correctly, they are a go on to guess the next When the user guesses one bit incorrectly, they have to go back to the beginning of the sequence and enter the first bit again Example output: The correct sequence is 0-0-1-1 $ ./launcher (The answer is 12) Starting from the beginning: What would you like your next guess to be: 0 or 1? 0 (lucky guess of 1st bit) position 0: userBit 0, correctBit 0 Yay! That was right! What would you like your next guess to be: 0 or 1? 0 (lucky guess of 2nd bit) position 1: userBit 0, correctBit 0 Yay! That was right! What would you like your next guess to be: 0 or 1? 0 (Oops! This bit is wrong!) position 2: userBit 0, correctBit 1 Oops! That was wrong. Please restart from the beginning. Re-starting from the beginning: What would you like your next guess to be: 0 or 1? 0 (We know this bit from our earlier correct guess) position 0: userBit 0, correctBit 0 Yay! That was right! What would you like your next guess to be: 0 or 1? 0 (We know this bit from our earlier correct guess) position 1: userBit 0, correctBit 0 Yay! That was right! What would you like your next guess to be: 0 or 1? 1 (We know this bit from our earlier incorrect guess, must be opposite) position 2: userBit 1, correctBit 1 Yay! That was right! What would you like your next guess to be: 0 or 1? 0 (Oops! This last bit is wrong!) position 3: userBit 0, correctBit 1 Oops! That was wrong. Please restart from the beginning. Re-starting from the beginning: What would you like your next guess to be: 0 or 1? 0 (We know this bit from our earlier correct guess) position 0: userBit 0, correctBit 0 Yay! That was right! What would you like your next guess to be: 0 or 1? 0 (We know this bit from our earlier correct guess) position 1: userBit 0, correctBit 0 Yay! That was right! What would you like your next guess to be: 0 or 1? 1 (We know this bit from our earlier incorrect guess) position 2: userBit 1, correctBit 1 Yay! That was right! What would you like your next guess to be: 0 or 1? 1 (We know this bit from our earlier incorrect guess) position 3: userBit 1, correctBit 1 answerer finished Congratulations! You found it! guesser finished launcher finished The user has a time limit (NUM_SECONDS seconds) to find this pattern, or else the game ends automatically: $ ./launcher (The answer is 1) What would you like your next guess to be: 0 or 1? (I do not type anything and wait NUM_SECONDS seconds) answerer finished Oh no! The time is up! guesser finished launcher finished Please finish this single application implemented with 3 programs: launcher.c The program will have 3 global vars: answererPid, guesserPid, and shouldRun. shouldRun should be initialized to 1. Its main() install two signal handlers: one for SIGALRM and one for SIGCHLD. The SIGALRM handler will tell the two child processes to stop by sending them TIME_OVER_SIGNAL. It also sets shouldRun to 0. The SIGCHLD does a waitpid() in a loop to get all finished children. It also sets shouldRun to 0. After installing the signal handlers, main() launches first the answering program, and then the guessing program. When launching the answering program put the child pid in answererPid and have the child run the string constant ANSWERER_PROGNAME. When launching the guessing program put the child pid in guesserPid and have the child run the string constant GUESSER_PROGNAME. The guesser program must be told the process id of the answering process. Turn that to the string line[] with the following code: char line[LINE_LEN]; snprintf(line,LINE_LEN,"%d",answererPid); Be sure to pass line to the guesser. Then main() sets its self up to receive SIGALRM in NUM_SECONDS seconds. Lastly main() just does the following: while (shouldRun) sleep(1); sleep(1); sleep(1); printf("launcher finished "); return(EXIT_SUCCESS); guesser.c guesser.c should also have a global int shouldRun variable initialized to 1. Its main() should make sure it has a command line argument (exiting with EXIT_FAILURE if not). It should that argument is the process id of the answerer. Convert it from a string to an integer and hold on to its value. Then, main() should install 4 signal handler: The handler for TIME_OVER_SIGNAL announces that the time is up and sets shouldRun to 0. The handler for WIN_SIGNAL announces that the user won and sets shouldRun to 0. The handler for CORRECT_SIGNAL announces that the user got their last guess correct. The handler for INCORRECT_SIGNAL announces that the user got their last guess wrong, and should start again from the beginning. NOTE: Perhaps you can make the same handler handle both CORRECT_SIGNAL and INCORRECT_SIGNAL. In a while(shouldRun) loop, allow the user to enter their next guess. If they enter 0 send the answerer ZERO_SIGNAL. If they enter 1 send the answerer ONE_SIGNAL. At after sending the signal, do a sleep(1) to give the answerer time to respond. After the loop just do: printf("guesser finished "); return(EXIT_SUCCESS); assign2Headers.h Just copy-and-paste the following: /*-------------------------------------------------------------------------* *--- ---* *--- assign2Headers.h ---* *--- ---* *--- This file includes standard headers and declares constants ---* *--- common to the assignment 2 C programs. ---* *--- ---* *--- ---- ---- ---- ---- ---- ---- ---- ---- ---* *--- ---* *--- Version 1a 2018 February 5 Joseph Phillips ---* *--- ---* *-------------------------------------------------------------------------*/ //--- Common standard header files ---// #include #include #include #include #include #include #include //--- Common constants: ---// #define ZERO_SIGNAL SIGUSR1 #define ONE_SIGNAL SIGUSR2 #define CORRECT_SIGNAL SIGUSR1 #define INCORRECT_SIGNAL SIGUSR2 #define WIN_SIGNAL SIGINT #define TIME_OVER_SIGNAL SIGTERM #define GUESSER_PROGNAME "guesser" #define ANSWERER_PROGNAME "answerer" #define LINE_LEN 256 #define NUM_SECONDS 30 answerer.c Just copy-and-paste the following: /*-------------------------------------------------------------------------* *--- ---* *--- answerer.c ---* *--- ---* *--- This file defines the answerer program for assignment #2. ---* *--- ---* *--- ---- ---- ---- ---- ---- ---- ---- ---- ---* *--- ---* *--- Version 1a 2018 February 5 Joseph Phillips ---* *--- ---* *-------------------------------------------------------------------------*/ //--- Inclusion of header files ---// #include "assign2Headers.h" //--- Definition of constants: ---// #define PATTERN_LEN 4 //--- Definition of global vars: ---// int answer; int numCorrect = 0; int shouldRun = 1; //--- Definition of global fncs: ---// void timeUpHandler (int sig ) { shouldRun = 0; } void guessHandler (int sig, siginfo_t* infoPtr, void* dataPtr ) { int toSendBack; int userBit = (sig == ONE_SIGNAL); int correctBit = ((answer >> numCorrect) & 0x1); int isCorrect = (correctBit == userBit); printf("position %d: userBit %d, correctBit %d ", numCorrect,userBit,correctBit ); if (isCorrect) { numCorrect++; if (numCorrect >= PATTERN_LEN) toSendBack = WIN_SIGNAL; else toSendBack = CORRECT_SIGNAL; } else { numCorrect = 0; toSendBack = INCORRECT_SIGNAL; } kill(infoPtr->si_pid,toSendBack); } int main (int argc, char* argv[] ) { // I. Application validity check: // II. Run program: // II.A. Initialize random number generator and choice: srand(getpid()); answer = rand() % (1 << PATTERN_LEN); printf("(The answer is %d) ",answer); // II.B. Install signal handlers: struct sigaction act; memset(&act,'\0',sizeof(act)); act.sa_handler = timeUpHandler; sigaction(TIME_OVER_SIGNAL,&act,NULL); act.sa_flags = SA_SIGINFO; act.sa_sigaction = guessHandler; sigaction(ZERO_SIGNAL,&act,NULL); sigaction(ONE_SIGNAL,&act,NULL); // II.C. Hand out while game still active: while ( (numCorrect < PATTERN_LEN) && shouldRun ) sleep(1); // III. Finished, return answer: printf("answerer finished "); return(EXIT_SUCCESS); }

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