On 2022-04-27 22:45:09 -0400, Stefan Monnier wrote:
> Another option might be that your system's time was "reset".
> This shouldn't happen, but it can happen if your NTP was down, the
> machine got out-of-sync over time and you restart the NTP server at
> which point it may(!) decide to jump the clock if the difference is
> large enough (i.e. too large to catch up gradually).
> Can't remember how large is "large enough".
I don't think that systemd does that. Anyway, even if this were
possible, that would make the output inconsistent. I recall:
cventin:~/software/mpfr[1]> lt|head <14:43:42
total 7016
-rw-r--r-- 1 188644 2022-04-26 14:43:42 config.log
-rw-r--r-- 1 2861 2022-04-26 14:43:42 conftest.c
-rw-r--r-- 1 0 2022-04-26 14:43:42 conftest.err
-rw-r--r-- 1 1907 2022-04-26 14:43:42 confdefs.h
-rwxr-xr-x 1 632161 2022-04-26 14:43:16 configure.lineno*
drwxr-xr-x 2 4096 2022-04-26 14:43:11 doc/
drwxr-xr-x 3 4096 2022-04-26 14:43:11 tune/
-rwxr-xr-x 1 23568 2022-04-26 14:43:11 depcomp*
drwxr-xr-x 5 36864 2022-04-26 14:43:11 tests/
cventin:~/software/mpfr> lt|head <14:43:47
total 6416
-rw-r--r-- 1 19436 2022-04-26 14:43:47 config.log
-rw-r--r-- 1 561 2022-04-26 14:43:47 conftest.c
-rw-r--r-- 1 0 2022-04-26 14:43:47 conftest.err
-rw-r--r-- 1 4138 2022-04-26 14:43:47 mpfrtests.cfgout
-rw-r--r-- 1 500 2022-04-26 14:43:47 confdefs.h
-rwxr-xr-x 1 632161 2022-04-26 14:43:45 configure.lineno*
-rw-r--r-- 1 878 2022-04-26 14:43:45 mpfrtests.cventin.lip.ens-lyon.fr.out
drwxr-xr-x 3 4096 2022-04-26 14:43:44 tune/
drwxr-xr-x 4 36864 2022-04-26 14:43:44 tests/
where mpfrtests.cventin.lip.ens-lyon.fr.out was actually created
a fraction of second before configure.lineno in the script.
"14:43:42" is the time I ran the first "lt|head" and "14:43:47"
is the time I ran the second "lt|head", where "lt" is ls with
various options, including "-t" to sort in decreasing date order.
With time jumps, this is theoretically possible, but this would
mean that the time jumped at least 3 times:
1. To make the birth time as 14:43:45.
2. To make the last modified time earlier than 14:43:11 (so that
mpfrtests.cventin.lip.ens-lyon.fr.out doesn't appear in the
first "lt|head" output).
3. To go back after 14:43:42.
And this would not explain the
cventin:~/software/mpfr> tail -n 30 mpfrtests.*.out; ll mpfrtests.*.out
zsh: no match
zsh: no match
cventin:~/software/mpfr[1]> tail -n 30 mpfrtests.*.out; ll mpfrtests.*.out
zsh: no match
zsh: no match
which I did a few seconds before 14:43:42.
If the time did not jump, then the birth time 14:43:45.537241731
matches the behavior I've observed in the above commands, i.e. as if
this file were created at this time.
--
Vincent Lefèvre <vinc...@vinc17.net> - Web: <https://www.vinc17.net/>
100% accessible validated (X)HTML - Blog: <https://www.vinc17.net/blog/>
Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)
