……  [源創]文件copy命令的源代碼 
/*
  Name: x_copy.c
  Author: x-bit at 167168.kmip.net(純技術論壇) 
  Description: 文件copy命令，只能copy 一個文件。
               用法：命令 源文件 目標文件 
               dev-cpp5 + win2k下調試通過; 
               轉載請保留文章的完整性. 
  Date: 08-11-2004
  Copyright: x-bit(三哥) Allrights Reserved. 
*/

#include <stdio.h>
void usage(char *msg)
{
    puts(msg);
    puts("usage: command source target");
    exit(0);
}
void errMsg(char *msg)
{
    puts("File operation failure.");
    puts(msg);
    exit(0);
}
int main(int argc, char *argv[])
{
    FILE *si, *di;
    if(argc==1)
    {
        usage("parameter error");
    }
    else if(argc==2)
    {
        if(si=fopen(argv[1], "rb"))
            usage("Unable copy to itself.\ncopy 0 file.");
        else
            usage("can't open the file");
    }
    else if(argc>3)
    {
        usage("parameter error");
    }
    
    if(!(si=fopen(argv[1], "rb")))
        errMsg("can't open the file");
    if(!(di=fopen(argv[2], "wb")))
        errMsg("can't creat the file");
    while(!feof(si))
        fputc(fgetc(si), di);
        
    fclose(si);
    fclose(di);
    puts("copyed 1 file.");    
    return 0;
}