如何在 Bash/Debian 中获得文件创建日期/时间?

我正在 Debian GNU/Linux 6.0上使用 Bash。是否可以得到文件创建日期/时间? 不是修改日期/时间。 ls -lh a.txtstat -c %y a.txt都只给出了修改时间。

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Creation date/time is normally not stored. So no, you can't.

Unfortunately your quest won't be possible in general, as there are only 3 distinct time values stored for each of your files as defined by the POSIX standard (see Base Definitions section 4.8 File Times Update)

Each file has three distinct associated timestamps: the time of last data access, the time of last data modification, and the time the file status last changed. These values are returned in the file characteristics structure struct stat, as described in <sys/stat.h>.

EDIT: As mentioned in the comments below, depending on the filesystem used metadata may contain file creation date. Note however storage of information like that is non standard. Depending on it may lead to portability problems moving to another filesystem, in case the one actually used somehow stores it anyways.

Note that if you've got your filesystem mounted with noatime for performance reasons, then the atime will likely show the creation time. Given that noatime results in a massive performance boost (by removing a disk write for every time a file is read), it may be a sensible configuration option that also gives you the results you want.

mikyra's answer is good. The fact just like what he said.

[jason@rh5 test]$ stat test.txt
File: `test.txt'
Size: 0               Blocks: 8          IO Block: 4096   regular empty file
Device: 802h/2050d      Inode: 588720      Links: 1
Access: (0664/-rw-rw-r--)  Uid: (  500/   jason)   Gid: (  500/   jason)
Access: 2013-03-14 01:58:12.000000000 -0700
Modify: 2013-03-14 01:58:12.000000000 -0700
Change: 2013-03-14 01:58:12.000000000 -0700

if you want to verify, which file was created first, you can structure your file name by appending system date when you create a series of files.

ls -i menus.xml

94490 menus.xml Here the number 94490 represents inode

Then do a:

df -h

Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/vg-root   4.0G  3.4G  408M  90% /
tmpfs                 1.9G     0  1.9G   0% /dev/shm
/dev/sda1             124M   27M   92M  23% /boot
/dev/mapper/vg-var    7.9G  1.1G  6.5G  15% /var

To find the mounting point of the root "/" filesystem, because the file menus.xml is on '/' that is '/dev/mapper/vg-root'

debugfs -R 'stat <94490>' /dev/mapper/vg-root

The output may be like the one below:

debugfs -R 'stat <94490>' /dev/mapper/vg-root

debugfs 1.41.12 (17-May-2010)
Inode: 94490   Type: regular    Mode:  0644   Flags: 0x0
Generation: 2826123170    Version: 0x00000000
User:     0   Group:     0   Size: 4441
File ACL: 0    Directory ACL: 0
Links: 1   Blockcount: 16
Fragment:  Address: 0    Number: 0    Size: 0
ctime: 0x5266e438 -- Wed Oct 23 09:46:48 2013
atime: 0x5266e47b -- Wed Oct 23 09:47:55 2013
mtime: 0x5266e438 -- Wed Oct 23 09:46:48 2013
Size of extra inode fields: 4
Extended attributes stored in inode body:
selinux = "unconfined_u:object_r:usr_t:s0\000" (31)
BLOCKS:
(0-1):375818-375819
TOTAL: 2

Where you can see the creation time:

ctime: 0x5266e438 -- Wed Oct 23 09:46:48 2013
ls -i file #output is for me 68551981
debugfs -R 'stat <68551981>' /dev/sda3 # /dev/sda3 is the disk on which the file exists


#results - crtime value
[root@loft9156 ~]# debugfs -R 'stat <68551981>' /dev/sda3
debugfs 1.41.12 (17-May-2010)
Inode: 68551981   Type: regular    Mode:  0644   Flags: 0x80000
Generation: 769802755    Version: 0x00000000:00000001
User:     0   Group:     0   Size: 38973440
File ACL: 0    Directory ACL: 0
Links: 1   Blockcount: 76128
Fragment:  Address: 0    Number: 0    Size: 0
ctime: 0x526931d7:1697cce0 -- Thu Oct 24 16:42:31 2013
atime: 0x52691f4d:7694eda4 -- Thu Oct 24 15:23:25 2013
mtime: 0x526931d7:1697cce0 -- Thu Oct 24 16:42:31 2013
**crtime: 0x52691f4d:7694eda4 -- Thu Oct 24 15:23:25 2013**
Size of extra inode fields: 28
EXTENTS:
(0-511): 352633728-352634239, (512-1023): 352634368-352634879, (1024-2047): 288392192-288393215, (2048-4095): 355803136-355805183, (4096-6143): 357941248-357943295, (6144
-9514): 357961728-357965098

As @mikyra explained, creation date time is not stored anywhere.

All the methods above are nice, but if you want to quickly get only last modify date, you can type:

ls -lit /path

with -t option you list all file in /path odered by last modify date.

If you really want to achieve that you can use a file watcher like inotifywait.

You watch a directory and you save information about file creations in separate file outside that directory.

while true; do
change=$(inotifywait -e close_write,moved_to,create .)
change=${change#./ * }
if [ "$change" = ".*" ]; then ./scriptToStoreInfoAboutFile; fi
done

As no creation time is stored, you can build your own system based on inotify.

You can find creation time - aka birth time - using stat and also match using find.
We have these files showing last modified time:

$ ls -l --time-style=long-iso | sort -k6
total 692
-rwxrwx---+ 1 XXXX XXXX 249159 2013-05-31 14:47 Getting Started.pdf
-rwxrwx---+ 1 XXXX XXXX 275799 2013-12-30 21:12 TheScienceofGettingRich.pdf
-rwxrwx---+ 1 XXXX XXXX  25600 2015-05-07 18:52 Thumbs.db
-rwxrwx---+ 1 XXXX XXXX 148051 2015-05-07 18:55 AsAManThinketh.pdf

To find files created within a certain time frame using find as below.
Clearly, the filesystem knows about the birth time of a file:

$ find -newerBt '2014-06-13' ! -newerBt '2014-06-13 12:16:10' -ls
20547673299906851  148 -rwxrwx---   1 XXXX XXXX   148051 May  7 18:55 ./AsAManThinketh.pdf
1407374883582246  244 -rwxrwx---   1 XXXX XXXX   249159 May 31  2013 ./Getting\ Started.pdf


We can confirm this using stat:

$ stat -c "%w %n" * | sort
2014-06-13 12:16:03.873778400 +0100 AsAManThinketh.pdf
2014-06-13 12:16:04.006872500 +0100 Getting Started.pdf
2014-06-13 12:16:29.607075500 +0100 TheScienceofGettingRich.pdf
2015-05-07 18:32:26.938446200 +0100 Thumbs.db


stat man pages explains %w:

%w     time of file birth, human-readable; - if unknown

Cited from https://unix.stackexchange.com/questions/50177/birth-is-empty-on-ext4/131347#131347 , the following shellscript would work to get creation time:

get_crtime() {
for target in "${@}"; do
inode=$(stat -c %i "${target}")
fs=$(df "${target}"  | tail -1 | awk '{print $1}')
crtime=$(sudo debugfs -R 'stat <'"${inode}"'>' "${fs}" 2>/dev/null | grep -oP 'crtime.*--\s*\K.*')
printf "%s\t%s\n" "${target}" "${crtime}"
done
}

even better:

lsct ()
{
debugfs -R 'stat <'`ls -i "$1" | (read a b;echo -n $a)`'>' `df "$1" | (read a; read a b; echo "$a")` 2> /dev/null | grep --color=auto crtime | ( read a b c d;
echo $d )
}

lsct /etc

Wed Jul 20 19:25:48 2016

Another trick to add to your arsenal is the following:

$ grep -r "Copyright" /<path-to-source-files>/src

Generally speaking, if one changes a file they should claim credit in the “Copyright”. Examine the results for dates, file names, contributors and contact email.

example grep result:

/<path>/src/someobject.h: * Copyright 2007-2012 <creator's name> <creator's email>(at)<some URL>>
stat -c %w a.txt

%w returns the file creation(birth) date if it is available, which is rare.

Here's the link