Systémové programovanie domáca č. 2 - riesenie

Created: 2010-03-14 - 18:05

time ./a.out

real    0m4.106s
user    0m0.542s
sys     0m1.639s

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
/**
Funkcia pre zapisovanie a citanie rodicom - posiela data a potom caka na potvrdenie
*/
void parents(const char* message, FILE* stream, FILE* sstream) {
    int c = 1000;
    while(--c>0){
        char buffer[1024];
        fprintf(stream,"%s\n",message);
        fflush(stream);
        fgets(buffer,1024,sstream);
        //fputs(buffer,stdout); //nechceme spomalit vypisom
    }
}

/**
Funkcia pre zapisovanie a citanie dietatom - prijma data a posiela potvrdenie
*/
void childs(const char* message, FILE* stream, FILE* sstream) {
    int c = 1000;
    while(--c>0){
        char buffer[1024];
        fgets(buffer,1024,sstream);
        //fputs(buffer,stdout); //nechceme spomalit vypisom
        fprintf(stream,"%s\n",message);
        fflush(stream);
    }
}

int main() {
    pid_t pid;
    int fds[2]; //dve polia na file descriptory
    int fdss[2];
    pipe(fds); //dve pipe-i
    pipe(fdss);
    pid = fork(); //pid procesu
    if (pid == (pid_t) 0) {
        /* child */
        FILE* stream;
        FILE* sstream;
        
        stream = fdopen(fds[0],"r"); //otvorenie jednotlivych streamov na citanie a zapis
        sstream = fdopen(fdss[1],"w");
        
        childs("Dik za data.",sstream,stream);
        
        close(fds[1]); //uzavretie fds
        close(fdss[0]);
        close(fds[0]);
        close(fdss[1]);
        
        waitpid (pid, NULL, 0); //ukoncenie dietata
    } else {
        /* parent */
        FILE* stream;
        FILE* sstream;

        stream = fdopen(fds[1],"w"); //otvorenie jednotlivych streamov na zapis a citanie
        sstream = fdopen(fdss[0],"r");

        parents("Posielam data.",stream,sstream);

        close(fds[0]); //uzavretie fds
        close(fdss[1]);
        close(fds[1]);
        close(fdss[0]);
        
        waitpid (pid, NULL, 0); //ukoncenie dietata
    }
    return 0;
}