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### 2628. [filesys.ts] [PDTS] Possible `last_write_time()` postcondition?

Section: 15.25 [filesys.ts::fs.op.last_write_time] Status: NAD Submitter: GB-15 Opened: 2014-01-20 Last modified: 2016-08-10

Priority: Not Prioritized

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Discussion:

Addresses: filesys.ts

The constraint on `last_write_time` is too weak: It is noted that the postcondition of `last_write_time(p) == new_time` is not specified since it might not hold for file systems with coarse time granularity.

However, might it be possible to have a postcondition that `last_write_time(p) <= new_time` ?

Add postcondition: `last_write_time(p) <= new_time`

[2014-02-09, Beman Dawes comments:]

That assumes the file system rounds down. We don't know which direction a file system rounds. Nice try, but this one looks NAD to me.

[2014-02-13 LWG/SG-3 Issaquah: No consensus for change.]

Proposed resolution: