Существуют два man
страницы о sync
инструмент:
(1) http://man7.org/linux/man-pages/man1/sync.1.html
NAME
sync - Synchronize cached writes to persistent storage
SYNOPSIS top
sync [OPTION] [FILE]...
DESCRIPTION top
Synchronize cached writes to persistent storage
If one or more files are specified, sync only them, or their
containing file systems.
-d, --data
sync only file data, no unneeded metadata
-f, --file-system
sync the file systems that contain the files
--help display this help and exit
--version
output version information and exit
(2) http://manpages.ubuntu.com/manpages/trusty/en/man8/sync.8.html
NAME
sync - synchronize data on disk with memory
SYNOPSIS
sync [--help] [--version]
DESCRIPTION
sync writes any data buffered in memory out to disk. This can include
(but is not limited to) modified superblocks, modified inodes, and
delayed reads and writes. This must be implemented by the kernel; The
sync program does nothing but exercise the sync(2) system call.
The kernel keeps data in memory to avoid doing (relatively slow) disk
reads and writes. This improves performance, but if the computer
crashes, data may be lost or the filesystem corrupted as a result.
sync ensures that everything in memory is written to disk.
sync should be called before the processor is halted in an unusual
manner (e.g., before causing a kernel panic when debugging new kernel
code). In general, the processor should be halted using the
shutdown(8) or reboot(8) or halt(8) commands, which will attempt to put
the system in a quiescent state before calling sync(2). (Various
implementations of these commands exist; consult your documentation; on
some systems one should not call reboot(8) and halt(8) directly.)
Первый - от coreutils
в то время как второе от fileutils
. Я пытался скомпилировать sync
инструмент от coreutils 8.29
в Ubuntu 14.04, но получил то же sync
как (2).
Как я добираюсь sync
инструмент с функциональностью (1) на Ubuntu 14.04?
sync
в Ubuntu от coreutils
. Проверьте пакет, из которого это прибывает. sync
описанный в sync(8)
старинные вещи, которые, вероятно, никогда не были доступны на Ubuntu как часть fileutils
:
This page describes sync as found in the fileutils-4.0 package; other
versions may differ slightly.
sync(1)
страница справочника для - то, на что необходимо смотреть: 14.04, 18.04. Отметьте, как 18.04's страница справочника точно так же, как страница справочника man7.org.
Если Вы скомпилировали sync
от coreutils 8.29 и не получил те опции, Вы сделали что-то не так, с тех пор на Ubuntu 16.04, со значением по умолчанию sync
от coreutils 8.25 я действительно получаю те опции:
~ sync --help
Usage: sync [OPTION] [FILE]...
Synchronize cached writes to persistent storage
If one or more files are specified, sync only them,
or their containing file systems.
-d, --data sync only file data, no unneeded metadata
-f, --file-system sync the file systems that contain the files
--help display this help and exit
--version output version information and exit
GNU coreutils online help: <http://www.gnu.org/software/coreutils/>
Full documentation at: <http://www.gnu.org/software/coreutils/sync>
or available locally via: info '(coreutils) sync invocation'
~ sync --version
sync (GNU coreutils) 8.25
Copyright (C) 2016 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Written by Jim Meyering and Giuseppe Scrivano.