文件切割

 

下面是切割文件和合并文件的代码，是我用来熟悉文件操作函数时写的一些东西，大有完善的余地，与大家分享，听取大家指教。程序在UNIX_AIX下调试通过。

/***************************

mycut.c

文件切割程序

用于将文件切割成1024字节大小的小文件

***************************/

#include<stdio.h>

#include<stdlib.h>

#include<sys/stat.h>

 

#define SIZE 1024

#define MAX 1048576*5

main(int argc, char **argv)

{

       char buffer[SIZE],c;

       FILE *source, *target;

       struct stat sbuf;

       int count = 0, n = 0;

       char flag = '0';

       char mycount[10];

       char parts[10];

       char mysign[20];

      

 

       if(argc != 2)

       {

              fprintf(stderr, "Usage: source--file/n", *argv);

              exit(1);

       }

 

       if((source = fopen(argv[1],"r")) == NULL)

       {

              perror(argv[1]);

              exit(1);

       }

 

       stat(argv[1], &sbuf);

       if(sbuf.st_size > MAX)

       {

              printf("the file is too big /n");

              exit(0);

       }

 

       /*计算文件的块数*/

       count = sbuf.st_size / SIZE + 1;

       memset(mysign, 0, 10);

       printf("%d/n", count);

       /*记录文件个数*/

       target = fopen("thecount","w");

       sprintf(mysign, "%d", count);

       fputs(mysign, target);

       fclose(target);

       /*记录文件名*/

       target = fopen("thefilename","w");

       fputs(argv[1], target);

       fclose(target);

       for(flag=0; flag<count; flag++)

       {

              sprintf(mysign,"%d",flag);

              printf("%s",mysign);

              target = fopen(mysign, "w");

              n = fread(buffer, sizeof(char), SIZE, source);

              fwrite(buffer, sizeof(char), n, target);

              fclose(target);

 

       }

       fclose(source);

       exit(0);

}

/***************************

mycomb.c

文件合并程序

用于将用上面程序切割的小文件合并复原

***************************/

 

#include<stdio.h>

#include<stdlib.h>

#include<sys/stat.h>

 

#define SIZE 1024

#define MAX 1048576*5

main(int argc, char **argv)

{

       char buffer[SIZE],c;

       FILE *source, *target;

       struct stat sbuf;

       int count = 0, n = 0;

       char flag = '0';

       char mycount[10];

       char filename[20];

       char mysign[10];

       /*获得文件块数信息*/

 

       if((source = fopen("thecount","r")) == NULL)

       {

              printf("some thing is wrong/n");

              exit(1);

       }

       memset(mycount, 0, 10);

       fgets(mycount,10,source );

       fclose(source);

       remove("thecount");

       count = atoi(mycount);

       /*获得文件名信息*/

       if((source = fopen("thefilename","r")) == NULL)

       {

              printf("some thing is wrong/n");

              exit(1);

       }

       memset(filename, 0, 20);

       fgets(filename,10,source );

       fclose(source);

       remove("thefilename");

       target = fopen(filename,"a");

       memset(mysign, 0 ,10);

/*文件合并*/

       for(flag=0; flag<count; flag++)

       {

              sprintf(mysign,"%d",flag);

              printf("%s",mysign);

              source = fopen(mysign, "r");

              n = fread(buffer, sizeof(char), SIZE, source);

              fwrite(buffer, sizeof(char), n, target);

              fclose(source);

              remove(mysign);

       }

       fclose(target);

       exit(0);

}