C语言相关文件操作

1.对已知文件进行分割。

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
FILE *in,*out;
char filename[256],ch,cfilename[256];
void depart()
{
 char ext[6][6]={
 "a.txt",
 "b.txt",
 "c.txt",
 "d.txt",
 "e.txt",
 "f.txt"};
 unsigned long int n=1,k,byte=0;
 unsigned int j=0,i=0;
 printf("input filename:\n");
 scanf("%s",filename);
 strcpy(cfilename,filename);
 if((in=fopen(filename,"r")) == NULL)
 {
  exit(0);
 }
 printf("file size:\n");
 scanf("%d",&n);
 n = n*1024;
 while(filename[j] != '.')
 {
  j++;
 }
 filename[j] = '\0';
 if((out=fopen(strcat(filename,ext[i]),"w")) == NULL)
 {
  exit(0);
 }
 
 fseek(in,0,2);
 k = ftell(in);
 fseek(in,0,0);
 while(k>0)
 {
  ch = fgetc(in);
  fputc(ch,out);
  byte++;
  k--;
  if(byte == n)
  {
   fclose(out);
   byte = 0;
   strcpy(filename,cfilename);
   while(filename[j] != '.')
   {
    j++;
   }
   filename[j]='\0';
   i++;
   if((out=fopen(strcat(filename,ext[i]),"w")) == NULL)
   {
    exit(0);
   }
  }
 }
 
 fclose(in);
 printf("depart success!\n");
}
int main()
{
 depart();
 return 0;
}

2.操作临时文件，新建文件（tcc编译器）

#include <stdio.h>
#include <io.h>
int main()
{
 /*临时文件的使用方法*/
 FILE *temp;
 char c;
 if((temp=tmpfile()) != NULL)
 {
  fputs("\nhello\nworld",temp);
 }
 rewind(temp);//文件指针返回文件头
 while((c = fgetc(temp)) != EOF)
 {
  printf("%c",c);
 }
 fclose(temp);
 /*新建文件的方法*/
 int handle;
 char filename[256];
 printf("input filename:\n");
 scanf("%s",filename);
 if((handle = creat(filename,0)) == -1)
 {//tcc中io.h文件中的creat函数，新建文件。
  printf("error!");
 }
 else
 {
  printf("Success");
  close(handle);
 }
}

本文就写这几个功能，其他再续……