简单cp

/* ============================================================================ Name        : cp.c Author      : mtt Version     : Copyright   : Your copyright notice Description : Hello World in C, Ansi-style ============================================================================ */#include <stdio.h>#include <stdlib.h>#include <string.h>int main(int argc ,char *argv[]) {FILE *file;FILE *stream;    char buffer[1024];if(   argc==1){puts("cp: 缺少了文件操作数");puts("use cp src dest");puts("for help cp --help");exit(0);}else{if(strcmp(argv[1],"--help")==0){puts( "\t用法：cp [选项]... [-T] 源文件 目标文件");puts("\t或：cp [选项]... 源文件... 目录");puts("\t或：cp [选项]... -t 目录 源文件...");puts("\t将源文件复制至目标文件，或将多个源文件复制至目标目录。");puts("\t -a, --archive等于-dR --preserve=all");puts("\t -n, --no-clobber不要覆盖已存在的文件(使前面的 -i 选项失效)");puts("\t -b类似--backup 但不接受参数");puts("\t -d等于--no-dereference --preserve=links");}else{if((file =fopen(argv[1],"r+"))==NULL){  printf("不存在%s文件。",argv[1]);  exit(-1);}if((stream =fopen(argv[2],"a+"))==NULL){   printf("%s文件不能打开。\n",argv[2]);  exit(-1);}   while (fgets(buffer,sizeof(buffer),file)!=NULL)   {fputs(buffer,stream);  }fclose (file);fclose(stream);            }}return EXIT_SUCCESS;}