SO - Test Procese - Sub

#include <stdlib.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <signal.h>
#include <string.h>
#include <fcntl.h>


int pid_c1;
int pid_c2;
int pid_c3;
int pid_p;
int status;
char litera;

void rutina_sc (int a) {
    int pid = wait(&status);
    printf("copil %d terminat cu %d\n", pid, WEXITSTATUS(status));
}

void rutina_alarm (int a) {
    printf("1\n");
    alarm(1);
}

void rutina_usr (int a) {
    printf("C\n");
}

int main (int argc, char* argv[]) {
    int pfd13[2], pfd23[2];
    char buff[1000];
    int contor_cifre=0;
    int buff_size;
    int i;

    pid_p = getpid();

    struct sigaction sigActSC;
    sigActSC.sa_handler = rutina_sc;
    sigActSC.sa_flags = 0;

    struct sigaction sigActUSR;
    sigActUSR.sa_handler = rutina_usr;
    sigActUSR.sa_flags = 0;

    struct sigaction sigActALR;
    sigActALR.sa_handler = rutina_alarm;
    sigActALR.sa_flags = 0;

    sigaction(SIGCHLD, &sigActSC, NULL);
    sigaction(SIGUSR1, &sigActUSR, NULL);

    if (argc != 3) {
        printf("wrong arguments\n");
        exit(-1);
    }

    if (pipe(pfd13) < 0) {
        printf("error pipe 1-3\n");
        exit(-2);
    }

    if (pipe(pfd23) < 0) {
        printf("error pipe 2-3\n");
        exit(-3);
    }

    if ((pid_c1 = fork()) < 0) {
        printf("error forking 1\n");
        exit(-4);
    } else if (pid_c1 == 0) {
        close(pfd13[0]);
        close(pfd23[0]);
        close(pfd23[1]);

        dup2(pfd13[1], 1);
        execlp("cat", "cat", argv[1], NULL);
        printf("\n");
        close(pfd13[1]);

        //kill(pid_p, SIGCHLD);
        exit(1);
    } else if ((pid_c2 = fork()) < 0) {
        printf("error forking 2\n");
        exit(-5);
    } else if (pid_c2 == 0) {
        close(pfd13[0]);
        close(pfd13[1]);
        close(pfd23[0]);

        dup2(pfd23[1], 1);
        execlp("cat", "cat", argv[2], NULL);
        printf("\n");
        close(pfd23[1]);
        //printf("ana");


        //kill(pid_p, SIGCHLD);
        exit(1);
    } else if ((pid_c3 = fork()) < 0) {
        printf("error forking 3\n");
        exit(-6);
    } else if (pid_c3 == 0) {
        close(pfd13[1]);
        close(pfd23[1]);

        while (buff_size = read(pfd13[0], &buff, 100)) {
            for(i=0; i<buff_size; i++) {
                if(buff[i] >= '0' && buff[i] <= '9') {
                    contor_cifre++;
                    if (kill(pid_p, SIGUSR1) == 0) {
                       //printf("error sigusr1\n");
                    }
                }
            }
        }
        close(pfd13[0]);

        while (buff_size = read(pfd23[0], &buff, 1000)) {
            for(i=0; i<buff_size; i++) {
                if(buff[i] >= '0' && buff[i] <= '9') {
                    contor_cifre++;
                    kill(pid_p, SIGUSR1);
                }
            }
        }
        close(pfd23[0]);

        //kill(pid_p, SIGCHLD);
        exit(contor_cifre);
    } else {
        close(pfd13[0]);
        close(pfd13[1]);
        close(pfd23[0]);
        close(pfd23[1]);

        sigaction(SIGALRM, &sigActALR, NULL);

        alarm(1);
        while(1);
        exit(4);
    }

}