Thread: MAC can read, but not write to WIN.

  1. #1
    Registered User Queatrix's Avatar
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    Post MAC can read, but not write to WIN.

    I was on an apple that had MAC and WIN on it. MAC can read files WIN partitions, but not write to them. And the error did not say why. Why is this? Copyright reasons?

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    Registered User rynoon's Avatar
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    As far as I know, Macs cannot safely write to an ntfs partition. So write permissions are most likely disabled. I could be wrong.

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    pwns nooblars
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    Hmmm there is no NTFS driver for Mac? I thought that Mac OS X is closer to its Unix roots, if that is so, then you should be able to find a driver for your NTFS needs, unless of course I am mistaken on how related they are.

    I have never owned a Mac nor have I delved too deeply into Mac OS X since my main exposure to Mac was public school and I graduated from that a couple years ago.

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    Registered User Queatrix's Avatar
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    But how can it read from an NTFS without the driver, yet it needs the driver to write? If it knows the format to read isn't that the same as knowing the format to write?

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    Hurry Slowly vart's Avatar
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    Quote Originally Posted by Queatrix
    But how can it read from an NTFS without the driver, yet it needs the driver to write? If it knows the format to read isn't that the same as knowing the format to write?
    it is not the same

    let's take the simple example. FAT format stores the list information in two copies of the FAT table...

    It is enough for reading to be able to locate the first instance and read info from it.

    to write - you should know how to locate the second copy of the FAT-table. Otherwise after your write operation the partition will be left in some inconsistant state...

    So as you see you can have only partial information about format and it will be suffitient for reading, but not for writing. To write - you need fully understand the format
    All problems in computer science can be solved by another level of indirection,
    except for the problem of too many layers of indirection.
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    &TH of undefined behavior Fordy's Avatar
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    Registered User code2d's Avatar
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    So as you see you can have only partial information about format and it will be suffitient for reading, but not for writing. To write - you need fully understand the format
    Does this mean is does not matter?

    sorry I am very slow when it comes to partitions even though I have overwritten my millnium 1000 times.
    Compiler in use: MinGW

    OS: Windows ME

  8. #8
    pwns nooblars
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    It means that you can read the data on a particular partition without having to know the full information on the partition type. But to write without corrupting the drive you need to have 100% knowledge.

  9. #9
    Cat without Hat CornedBee's Avatar
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    Also, you can't destroy anything by reading. If you make a mistake in reading, the worst you get is that the data you read is wrong. No lasting damage done. If you make a mistake in writing, you can destroy data.

    The open-source NTFS driver currently supports only very limited forms of writing. Effectively, it's a read-only driver: you can read NTFS partitions, but you can't write to them.
    All the buzzt!
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