count vowels kid/parent linux

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

#define VOWELS "aeiou"

int main(int argc, char *argv[]) {
    if (argc != 2) {
        fprintf(stderr, "Wrong usage!\n");
        exit(1);
    }
    int pbuff[2];
    if (pipe(pbuff)) {
        perror("pipe");
        exit(1);
    }
    pid_t pid = fork();
    if (pid == -1) {
        perror("");
        exit(-1);
    }
    if (pid == 0) {//kid
        close(pbuff[0]);
        int fd = open(argv[1], O_RDONLY);
        if (fd < 0) {
            perror("open");
            exit(1);
        }

        char ch;
        while (read(fd, &ch, 1)) {
            if (strchr(VOWELS, ch)) {
                write(pbuff[1], &ch, 1);
            }
        }
        close(fd);
        close(pbuff[1]);
        exit(0);
    }
    close(pbuff[1]);
    char ch;
    int cnt = 0;
    while (read(pbuff[0], &ch, 1)) {
        cnt++;
    }
    printf("Cnt: %d\n", cnt);
    close(pbuff[0]);
    int stat;
    wait(&stat);
    return 0;
}