I am writing a small linux shell in C and am so very close to being done. I take in a command from the user and store it in args, delimited by spaces. In the following example, let's say that args contains the following:

args[] = {"ls", "-l", "|", "wc"};

My function takes in args and also takes in how many pipes there are. I've commented my code as much as possible. Here it is:

int do_command(char **args, int pipes) {
    // The number of commands to run
    const int commands = pipes + 1;
    int i = 0;

    int pipefds[2*pipes];

    for(i = 0; i < pipes; i++){
        if(pipe(pipefds + i*2) < 0) {
            perror("Couldn't Pipe");
            exit(EXIT_FAILURE);
        }
    }

    int pid;
    int status;

    int j = 0;
    int k = 0;
    int s = 1;
    int place;
    int commandStarts[10];
    commandStarts[0] = 0;

    // This loop sets all of the pipes to NULL
    // And creates an array of where the next
    // Command starts

    while (args[k] != NULL){
        if(!strcmp(args[k], "|")){
            args[k] = NULL;
            // printf("args[%d] is now NULL", k);
            commandStarts[s] = k+1;
            s++;
        }
        k++;
    }



    for (i = 0; i < commands; ++i) {
        // place is where in args the program should
        // start running when it gets to the execution
        // command
        place = commandStarts[i];

        pid = fork();
        if(pid == 0) {
            //if not last command
            if(i < pipes){
                if(dup2(pipefds[j + 1], 1) < 0){
                    perror("dup2");
                    exit(EXIT_FAILURE);
                }
            }

            //if not first command&& j!= 2*pipes
            if(j != 0 ){
                if(dup2(pipefds[j-2], 0) < 0){
                    perror("dup2");
                    exit(EXIT_FAILURE);
                }
            
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