argon | An open-standards augmented reality platform for the web | Augmented Reality library

#include 
#include 
#include 
#include 
#include 

int funcone(){
    int i;
    char *arr[5] = {"One", "Two", "Three", "Four", "Five"};
    for(i = 0; i <= 5; i++){
        printf("%s\t%d\n", arr[i], i);
    }
    printf("\n~");
    return 1;
}

#define NCHAR 1024
#define DELIMIT "\t\n"
int functwo(){
    //prints only numbers from input received from funcone
    int c;
    int position = 0, nchar = NCHAR, i;
    char *arr = malloc(sizeof *arr * nchar);

    if (!arr)
    {
        fprintf(stderr, "Memory Exhausted.");
    }

    //reads input from stdin stream, supposedly piped from func1
    while ((c = fgetc(stdin)) != 126)
    {
        arr[position++] = c;

        if (position >= nchar) // reallocate space if needed
        {
            nchar += NCHAR;
            arr = realloc(arr, nchar + NCHAR);

            if (!arr)
            {
                fprintf(stderr, "Memory Exhausted.\n");
                break;
            }
        }
    }
    arr[position] = 0;

    char *token;
    //splits string by \t\n, and converts string into numbers
    token = strtok(arr, DELIMIT);
    while (token != NULL)
    {
        char *endptr;
        int x = strtol(token, &endptr, 10);
        if (x > 0)
        {
            printf("%d\n", x);
        }
        token = strtok(NULL, DELIMIT);
    }
    printf("\n~");

    free(arr);  

    return 1;
}

int main(){
    printf("piping begins\n");
    int fd[2];
    int childstatus = 0;
    
    if (pipe(fd) == -1)
    {
        perror("Pipe1 error");
        return 1;
    }

    int pid1 = fork();
    if (pid1 < 0)
    {
        perror("Pid1 error");
        return 1;
    }

    if (pid1 == 0)
    {
        //child 1 process
        dup2(fd[1], STDOUT_FILENO);
        close(fd[1]);
        close(fd[0]);
        int f1 = funcone();
        // int f1 = (*builtin_functions[aone])(argone);
        /*In the main program, this line runs a function 
         *with a corresponding index number, and takes in the
         *command keywords as arguments. Returns 1 to continue Shell loop, 0 to exit.*/
    }

    int pid2 = fork();
    if (pid2 < 0)
    {
        perror("Pid2 error");
        return 1;
    }

    if (pid2 == 0)
    {
        // child 2 process
        dup2(fd[0], STDIN_FILENO);
        dup2(fd[1], STDOUT_FILENO);
        close(fd[0]);
        close(fd[1]);
        int f2 = functwo();
        // int f1 = (*builtin_functions[aone])(argone);
    }

    // parent process

    waitpid(pid1, &childstatus, WNOHANG);
    waitpid(pid2, &childstatus, WNOHANG);

    dup2(fd[0], STDIN_FILENO);
    close(fd[0]);
    close(fd[1]);

    int f3 = functwo();
    //supposed to be functhree, but something similar to functwo so i reused it.
    // int f3 = (*builtin_functions[aone])(argone);
    printf("Piping process complete.\n");
}