Hello everyone, I'm new to C and was hoping ya'll could review my code. It is a simple workout program that prints a list of exercises into a .txt file.

The major bug is in main.c line 18 and the generateProgram function in boxing_functions.c line 57. I'm still learning pointers and have no one to ask for help other than forums lol. Thanks in advance for any and all help.


#include "boxing_hdr.h"

void main(void){

  int minutes, numSets;
  char fileName;

  printf("This program generates a boxing workout in a .txt file.\n");
  printf("How many minutes do you want to workout?");
  scanf("%d", &minutes);

  // This divides the time you entered into 3 minutes blocks and
  // returns how many sets you can workout for
  numSets = Time(minutes);

  // Prints outs the program to the new text
  // file and returns the name of the .txt file
  fileName = generateProgram(numSets);

  printf("Generation done, the workout is located in the \
          file named %s. Have fun and hit it hard\n", fileName);



#include "boxing_hdr.h"

// This divides the time you entered into 3 minutes blocks and
// returns how many sets you can workout for
int Time(int minutes){
  int sets;

  sets = minutes / 4;
  return sets;

// This function return the current time and date
// This is what the program will be named
char * Date(void){
  struct tm *local;
  time_t t;

  t = time(NULL);
  local = localtime(&t);
  return asctime(local);

// This function performs the actual shuffling of the array
void shuffle(int *array, size_t n){
  if (n > 1)
      size_t i;
      for (i = 0; i < n -1; i++)
      size_t j = i + rand() / (RAND_MAX / (n-i) + i);
      int t = array[j];
      array[j] = array[i];
      array[i] = t;

// This Function initializes the array shuffles the data (by calling shuffle())
void initializeExercises()
  int indices[length(data)];
  int i;

  // Initialize the indices
  for ( i = 0; i < length(data); ++i)
      indices[i] = i;

  // Shuffle the indices array
  shuffle(indices, length(data));

// This function generates and prints the program, returning the file name

char generateProgram(int sets){
  int fd, openFlags, i;
  int indices[length(data)];
  mode_t filePerms;
  char fileName[25];

  // Set permissions for the file and open it
  openFlags = O_CREAT | O_WRONLY;
  filePerms = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP |
              S_IROTH | S_IWOTH;

  fd = open(Date(), openFlags, filePerms);
  if(fd == -1)


  // Write to the file
  for ( i = 0; i < sets; i++)
      write(fd, data[indices[i]], strlen(data[indices[i]]));
      write(fd, "\n", 1);

  // Close the file
  if(close(fd) == -1)

  strcpy(fileName, Date());
  return fileName;

Here is the hdr.h file

#ifndef BOXING_HDR
#define BOXING_HDR

#define length(x) sizeof(x)/sizeof*(x)

#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <time.h>
#include <unistd.h>

static const char *data[] = 
    "Run 1 mile",
    "Jump Rope 3 Rounds",
    "Shadow Box",
    "heavy bag", 
    "push ups",

int Time(int minutes);

char * Date(void);

char generateProgram(int sets);

void initializeExercises();

void shuffle(int *array, size_t n);


I don't see anything wrong with any line 18.

When asking for help, you need to give details. What is the problem you see? You gave us a line, but is it the same line in the post? If not, use the numbers in the post.

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