#include <unistd.h>
#include <stdio.h>

typedef void* list_item;
typedef int(list_item) worker_func

int process_list(list_item* list_item_array, unsigned int length,
                 worker_func async_func, worker_func sync_func)
/* Beware: recursive fork ;)
   Dispatches async_func on last item of array in parallel with forked
   process doing same for (n-1)-th item of array;
   then waits for child process to finish and dispatches the sync_func
   Performance is fine: most shells limit the number of cmd args
*/
{
    pid_t pid = 0;
    if (length > 1) {
        // fork, baby, fork
        pid = fork();
        if (pid < 0)
            printf("Fork failed -- ABANDON SHIP\n");
        else if (pid == 0) // child process
            return process_list(list_item_array, length-1,
                                async_func, sync_func);
    }
    // actually do some stuff
    async_func(list_item_array[length-1]);
    if (pid) // wait for child to finish to execute sync_funcs synchronously
        waitpid(pid);
    sync_func(list_item_array[length-1]);

    return 0;
}