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Unix Cat in C

My crummy cat rewrite

Cat is a core utility from unix like operating systems that echoes the text you give it into ‘stdout’. You already know this, but have you ever wrote a clone of it? Most likely also yes because it’s a very nice way to understand file I/O in the language you are using. Here is my implementation 

/*
 * Crappy Cat 
 * Author exit0ne
 * Date Oct 16 24
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define ARGUMENT_ERROR 1
#define FILE_IO_ERROR 2

int main(int argc, char **argv)
{
  /* Muh variables */
  FILE  *filePtr;
  const char *filePath;
  char curChar;

  /* Muh Argsssss */
  if (argc < 2) {
    printf("Argument error\n");
    return ARGUMENT_ERROR;
  }

  /* Call the end user a big dummy for asking for help in this cruel world */
  if (strcmp(argv[1], "-h") == 0 || strcmp(argv[1], "--help") == 0
  || strcmp(argv[1], "-help") == 0 || strcmp(argv[1], "help") == 0) {
    puts("It's cat are you stupid?");
    puts("Why would you ever need help with this?");
    return 0;
  }

  /* Print ze files from ze argument vector and consume ze bugs */
  for (int i = 1; i < argc; ++i) {
    filePath = argv[i];
    filePtr = fopen(filePath, "r");
    if (filePtr == NULL) {
      printf("File I/O error\n");
      return FILE_IO_ERROR;
    }

    while ((curChar = fgetc(filePtr)) != EOF)
      putchar(curChar);

    fclose(filePtr);
  }

  return 0;
}

BUUUUUT!!!!

Even with a program as seemingly simple as cat, there are complexities. For example, there are a good number of arguments and functionalities from the POSIX standard for cat that I did not put into my clone.

WHY???!?!?!?!?!?!?!!?!?!?

I wrote this cat clone so I can get used to file I/O and to port to Golang. That’s it, have a good one, two, three, four, five, six, se………….