The correct syntax for a recursive chmod command in Terminal

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The correct syntax for a recursive chmod command in Terminal

I need to set recursive permissions on an external HDD to '777' or 'all read&write'.

I have tried all of the following commands in Terminal:

sudo chmod 777 -r /Volumes/...
sudo chmod -r 777 /Volumes/...
sudo chmod a+rw -r /Volumes/...
sudo chmod -r a+rw /Volumes/...

...all of which being back a 'no such file or directory' error, e.g.

sudo chmod 777 -r /Volumes/232Gb
chmod: -r: No such file or directory

Can anyone confirm the correct syntax for this command?

Thanks in advance...

Message was edited by: ChippyDeluxe

MacBook, Mac OS X (10.6.6)

Posted on Apr 7, 2011 4:36 AM

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Answer 1

Linc Davis

Level 10

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Apr 7, 2011 5:52 AM in response to ChippyDeluxe

Questions about the shell belong in the UNIX forum, but the answer is

sudo chmod -R 777 /Volumes/theVolume

This is almost certainly not what you should do, but that wasn't your question.

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Answer 2

ChippyDeluxe Author

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Apr 7, 2011 7:47 AM in response to Linc Davis

If there were a solution that didn't involve using Terminal, I would prefer that.

The reason I ask is, since my old iMac died and I connected my iMac's external HDD to my MacBook, thousands of folders on my external HDD have 'stop signs' on them and require me to go to

Get Info -> Sharing & Permissions

...and add my MacBook username and set the privilege as "read and write". A bigger problem is, no backup software I've tried will back up this external HDD onto another external HDD any more, so I no longer have an up-to-date backup, which is very worrying.

I am looking for a way of fixing this, and the chmod command appears to be the answer.

Ideally, I don't want any permission restrictions on my external HDD at all, so I can connect it to any machine without problems.

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Answer 3

Linc Davis

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Apr 7, 2011 7:53 AM in response to ChippyDeluxe

Open the info window on the volume, click the lock icon, enter your password, and check the box labeled "Ignore permissions on this disk." Do the same, if necessary, when you mount it on another Mac.

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Answer 4

ChippyDeluxe Author

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Apr 7, 2011 7:58 AM in response to Linc Davis

Thank you. I will try that

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Answer 5

ChippyDeluxe Author

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Apr 7, 2011 10:25 AM in response to Linc Davis

I thought I'd checked that but couldn't remember...

That drive is missing that option.

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Answer 6

Király

Level 6

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Apr 7, 2011 10:54 AM in response to ChippyDeluxe

777 will set the executable bit on everything, including files. You don't want the executable bit on files. It should be set on folders and scripts only. Also, you need a capital R for the recursive flag. Not a lower case r.

Try:

sudo chmod -R +rwX /Volumes/externaldrive

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Answer 7

ChippyDeluxe Author

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Apr 7, 2011 11:03 AM in response to Király

Thanks, however, that created a scrolling page with 1000s of 'Operation Not Permitted' errors

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Answer 8

Király

Level 6

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Apr 7, 2011 11:13 AM in response to ChippyDeluxe

Is it formatted HFS+? If it's formatted for Windows (NTFS) it will be read only until you erase it and reformat it for Mac OS X Extended.

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Answer 9

ChippyDeluxe Author

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Apr 7, 2011 11:26 AM in response to Király

No, it's definitely Mac formatted.

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Answer 10

Linc Davis

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Apr 7, 2011 2:27 PM in response to ChippyDeluxe

+That drive is missing that option.+

In the "General" section of the info window, do you see "Kind: Volume"?

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Answer 11

ChippyDeluxe Author

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Apr 7, 2011 2:30 PM in response to Linc Davis

Yes

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Answer 12

Linc Davis

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209,739 points

Apr 7, 2011 2:45 PM in response to ChippyDeluxe

Please launch Disk Utility, select the external hard drive (not the volume) and click the "Info" button in the toolbar. What does it show for "Partition Map Scheme" and for "Writable"?

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Answer 13

ChippyDeluxe Author

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Apr 7, 2011 2:55 PM in response to Linc Davis

'GUID Partition Table'

'Yes'

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Answer 14

Linc Davis

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Apr 7, 2011 3:08 PM in response to ChippyDeluxe

You must be using the drive as your Time Machine backup, then. Are you using the Finder to access the backup files?

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Answer 15

ChippyDeluxe Author

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Apr 7, 2011 3:11 PM in response to Linc Davis

Yes, I'm using it as my Time Machine backup. Sorry, should I have mentioned that?

No, I'm not attempting to access the Time Machine backup, just the other folders I have saved on the drive.

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