Re^2: Safely create new directory

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Re^3: Safely create new directory by BrowserUk (Patriarch) on Jul 26, 2012 at 14:51 UTC
nformation in this thread that mkdir is in fact atomic I don't believe that atomicity of mkdir was ever in doubt as far as local filesystems are concerned. The question, I thought, was about whether it remained atomic for NFS mounted directories. My point in posting was -- on ancient HP/UX, where mkdir was tested and found atomic on NFS-mounted drives -- not just that that simple form of loop was sufficient to obtain a unique directory, but actually that it is far more likely to be reliable than the two-stage mechanisms that create files first, then directories. Tendered with the clear caveat of the ancient state of my knowledge, I fail to see that creating a file -- just another name in the directory space -- is any more likely to be atomic than creating a directory. But ... that is based on logic alone; not current, OS-specific knowledge. With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice. The start of some sanity?	[reply]

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Re^3: Safely create new directory
by BrowserUk (Patriarch) on Jul 26, 2012 at 14:51 UTC

nformation in this thread that mkdir is in fact atomic

I don't believe that atomicity of mkdir was ever in doubt as far as local filesystems are concerned.

The question, I thought, was about whether it remained atomic for NFS mounted directories.

My point in posting was -- on ancient HP/UX, where mkdir was tested and found atomic on NFS-mounted drives -- not just that that simple form of loop was sufficient to obtain a unique directory, but actually that it is far more likely to be reliable than the two-stage mechanisms that create files first, then directories.

Tendered with the clear caveat of the ancient state of my knowledge, I fail to see that creating a file -- just another name in the directory space -- is any more likely to be atomic than creating a directory.

But ... that is based on logic alone; not current, OS-specific knowledge.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

"Science is about questioning the status quo. Questioning authority".

In the absence of evidence, opinion is indistinguishable from prejudice.

The start of some sanity?

[reply]