c - 二进制文件 I/O。 (感觉这个操作有心理障碍)

Question

我应该制作一个读取和写入二进制文件的 C 程序。它需要 2 个参数:

1. 输入文件的名称 (.wav)

2. 输出文件的名称 (.wav)

我需要读取输入 .wav 文件的前 44 个字节并将其写入输出 .wav 文件。然而，这对我来说是全新的，我已经观看了几个视频，但仍然没有完全掌握缓冲区、短裤、size_T 变量类型的概念。

这是我的问题，我知道您需要初始化两个指针(输入、输出文件)

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
int main(int argc, char **argv){

 if (argc != 2){
    fprintf(stderr, "Usage: %s <filename>\n", argv[0]);
    exit(1);
    }

  FILE *ipfile, *opfile;
  char *buffer;    //what does this even do? Apparently this is a block of memory that I will store what I read/write?

  ipfile = fopen(argv[1], "rb+");
  opfile = fopen(argv[2], "wb+");

  short first_44[44];   //i think this is where i'm storing the first 44 bytes?

  fread(&first_44, sizeof(short), 44, ipfile); //So i think that i'm reading from ipfile and reading up until 44 bytes and storing it in first_44 ?

  fwrite(&first_44, sizeof(short), 44, opfile); //I think this is just writing what was in first_44 to opfile

  fclose(ipfile);
  fclose(opfile);

  return 0;
  }

任何人都知道这段代码有什么问题，也许可以帮助我更好地理解 I/O(从二进制文件读取并将读取的内容写入另一个文件)

谢谢!

Answer 1

更正代码。

int main(int argc, char **argv)
{
    FILE *ipfile, *opfile;
    char *buffer;
    const int bytes = 44;

    if (argc != 3)
    {
        fprintf(stderr, "Usage: %s <filename>\n", argv[0]);
        return 0;
    }

//  open file
    ipfile = fopen(argv[1], "rb");
    opfile = fopen(argv[2], "wb");

//  check if files opened   
    if (!ipfile)
    {
        printf ("Error opening input file\n");
        return 0;
    }
    if (!opfile)
    {
        printf ("Error opening output file\n");
        fclose (ipfile);
        return 0;
    }

//  allocate memory
    buffer = malloc (bytes);

//  read input file
    if (fread (buffer, bytes, 1, ipfile)!=1 )
    {
        printf ("Error reading input file\n");
        fclose (ipfile);
        fclose (opfile);
        free (buffer);
        return 0;
    }

//  write out
    if (fwrite(buffer, bytes, 1, opfile)!=1 )
    {
        printf ("Error writing output file\n");
        fclose (ipfile);
        fclose (opfile);
        free (buffer);
        return 0;
    }

//  close files
    fclose(ipfile);
    fclose(opfile);
    free (buffer);

//  success 
    printf ("Done!\n");
    return 1;
}