Concurrent program in C(sequential issue) - c

Question

I am trying to find a way to make this algorithm run concurrent and be simultaneous. So far it has only 1 for-loop that reads each file and then makes a process for each file.
I believe this algorithm runs sequentially which is not what I want...
I thought about creating an outer for-loop where I put the wait(null) and read command. But when I tried it did not work, didn't produce output. Currently I have the wait(null) command in the parent process.
Any suggestions?
Code:
int main(int argc, char *argv[])
{
// ATTRIBUTES //
int freq[argc-1], ipc[argc][2], nbytes, i;// freq of words, pipes, counters
ssize_t errorfi;
char readbuffer[9999];
char** k = malloc(50);
char** op = malloc(50);
if(argc == ONE) { // there are no files given, throw error and close
fprintf(stderr, "There are no files found from %s\n", argv[0]);
exit(0);
}
for(i = 1; i < argc; i++) // creates pipes for ipc
pipe(ipc[i]);
pid_t pids[argc-1]; // array of pids
for(i = 1; i < argc; i++) { // reads input after position 0(a.out)
pid_t pid = fork(); // creates process
pids[i-1] = pid;
if( pid < 0 ) { // bad fork process: error
perror("bad fork");
exit(0);
}
else if(pid > 0) { //parent process
close(ipc[i][1]);
wait(NULL);
nbytes = read(ipc[i][0], readbuffer, sizeof(readbuffer));
if(nbytes > 0)
printf("%s\n", readbuffer);
}
else if(pid == 0) { // child process
close(ipc[i][0]);
k = inputReader(argv[i]); // finds filename,w1,w2,w3,uniqueWords
char info[50] = "";
strcat(info, k[0]);
strcat(info, " ");
strcat(info, k[1]);
strcat(info, " ");
strcat(info, k[2]);
strcat(info, " ");
strcat(info, k[3]);
strcat(info, " ");
strcat(info, k[4]);
int uniqueWordint = atoi(k[4]);
freq[i-1] = uniqueWordint; // freq of all uniqueWords
errorfi = write(ipc[i][1], info, strlen(info)+1); // writes info to pipe i
if (errorfi < 0 ) {
fprintf(stderr, "error found when writing in pipe errofi: %d\n", errorfi);
exit(0);
}
exit(0); // close process
} // closes child process
} // closes for-loop for each process
for(j = 0; j < argc-1; j++) {
wait(2); // if i put read command here it won't work
}
return(0); // close main
}

Answer 1

This is pretty much a sequential execution indeed. The parent-process enters a loop, forks a child-process, and then it won't continue to the next loop until that child-process is done.
What you could do is create a pid_t array of size argc, to store each fork()'s return value.
Also create a new loop after "for-loop for each process", where the parent-process would wait for all of his children, using wait(2) or waitpid(2), depending on whether you need to process each child's result in the specific order or not, and continue processing them (reading or whatever needed.