Objective-C:用命令行参数的格式对文件进行IO操作

 //  main.m

 //  03-copyFile

 //  Created by ma c on 15/8/24.

 //  Copyright (c) 2015年. All rights reserved.

 #import <Foundation/Foundation.h>

  int main(int argc, const char * argv[])

 {
     @autoreleasepool
     {
         //1、检查参数
         if(argc < )
         {
             NSLog(@"用法:命令行 源文件 目标文件");
             return -;
         }

         //2.检查源文件是否存在

         NSString *file1 = [NSString stringWithUTF8String:argv[]];

         NSString *file2 = [NSString stringWithUTF8String:argv[]];

         NSFileManager *fm = [NSFileManager defaultManager];

         BOOL isDirectory = YES;

         if(![fm fileExistsAtPath:file1 isDirectory:&isDirectory])
         {
             NSLog(@"源文件不存在");
             return -;
         }
         else
         {
             if(isDirectory)
             {
                 NSLog(@"不能拷贝目录");
                 return -;
             }

             //3.判断目标文件是否存在
             if(![fm fileExistsAtPath:file2 isDirectory:NULL])
             {
                 [fm createFileAtPath:file2 contents:nil attributes:nil];
             }
             else
             {
                 NSLog(@"是否要覆盖文件? 'y' or 'n'");
                 char answer = getchar();
                 if(answer != 'y')
                 {
                     return -;
                 }
             }

             //4.文件拷贝
             NSFileHandle *in = [NSFileHandle fileHandleForReadingAtPath:file1];

             NSFileHandle *out = [NSFileHandle fileHandleForWritingAtPath:file2];
             if(in && out)
             {
                 while(YES)
                 {
                     NSData *data = [in readDataOfLength:];
                     if(!data || [data length]<=)
                     {
                         break;
                     }
                     [out writeData:data];
                 }
             }
             else
             {
                 NSLog(@"文件打开失败");
             }

             //5.关闭文件
             [in closeFile];
             [out closeFile];
         }
     }
     return ;
 }