objective-c - objective-c : Error when using NSTask to unmount a USB drive

Question

问题是，当我使用 NSTask 卸载当前 USB 驱动器时，会出现以下错误:

    2013-06-03 09:39:41.096 NAME[1028:303] in moving file view controller
    dyld: DYLD_ environment variables being ignored because main executable    
    (/usr/sbin/diskutil) has __RESTRICT/__restrict section 
    Unmount of disk1 failed: at least one volume could not be unmounted

我的 mac 有分区，所以我认为 disk1 是 mac os。这是我用来卸载驱动器的函数:

    //When I call this function by passing all of these arguments:
    NSArray* arrayForCloseUSBDrive = [[NSArray arrayWithObjects:@"diskutil", @"unmountDisk",@"/Volumes/AAA/",nil]autorelease];
    [Utility handleDrive:@"/usr/bin/env" arrayArguments:arrayForCloseUSBDrive];

    //It will start run this function in Utility class:
    +(void)handleDrive:(NSString*)launchPath arrayArguments:(NSArray*)array
   {
      NSTask *task = [NSTask new];
      [task setLaunchPath:launchPath];
      [task setArguments:array];

      NSPipe *pipe = [NSPipe pipe];
      [task setStandardOutput:pipe];

      [task launch];
      [task waitUntilExit];
   }

Answer 1

找出无法卸载它的原因:

• 该卷是否由当前用户安装？

• 该卷中还有打开的文件吗？在终端中，fuser -uc/Volumes/MyMountPoint 将向您显示在该文件系统上打开文件的进程以及拥有它们的用户。只要打开任何文件，文件系统就无法卸载。