Is there a way to know the creation time of a file

问题:

i am using ubuntu and want to know the creation time of a file even when it gets modified or accessed ?

回答1:

Unfortunately Unix does not store the creation time of a file.

All you are able to get using stat is

1. time of last access
2. time of last modification
3. time of last status change

Note: When using filesystem type ext4 crtime is available!

回答2:

The closest attribute available is the "change time", also known as ctime. This is updated for various system calls, any that modify the inode, rather than the data it contains.

matt@stanley:~$ stat -c %z .bashrc 
2010-08-17 11:53:56.865431072 +1000

Links

• stat(1)
• stat(3)

回答3:

This little script can get the creation date for ext4:

#!/bin/sh

fn=`realpath $1`
echo -n "Querying creation time of $1..."
sudo debugfs -R "stat $fn" /dev/sda4|grep crtime

I named it fcrtime and put it in my ~/bin folder. So in any folder I can use the command like: fcrtime example.odp

Example output:

crtime: 0x5163e3f0:12d6c108 -- Tue Apr 9 12:48:32 2013

Compared to stat-ing the same file:

  File: `example.odp'
  Size: 54962       Blocks: 112        IO Block: 4096   regular file
Device: 804h/2052d  Inode: 11019246    Links: 1
Access: (0664/-rw-rw-r--)  Uid: ( 1000/   fulop)   Gid: ( 1000/   fulop)
Access: 2013-04-09 13:20:05.263016001 +0300
Modify: 2013-04-09 13:20:05.227016001 +0300
Change: 2013-04-09 13:20:05.227016001 +0300
 Birth: -

NOTES

1. realpath is usually not installed by default. In Ubuntu eg. install it with sudo apt-get install realpath
2. Replace /dev/sda4 if necessary with the one you get from mount|grep ext4

回答4:

According to http://en.wikipedia.org/wiki/Comparison_of_file_systems, this is available for ext4, btfrs, FAT, NTFS, and UDF filesystems, plus some others you're unlikely to encounter. It's not available on ext2 or ext3, probably the most common file system formats in Ubuntu.

You'll need a kernel patch, though: http://lwn.net/Articles/394391/. Apparently this is because Linus rejected creation time attribute on the grounds that somebody called it an "otime" and somebody else called it a "btime", and therefore the idea must be useless.

回答5:

Creation time, is known as file Birth time and is supported on some filesystem, with some kernels only. The command would be Mohsen Pahlevanzadeh answer:

stat --printf='%w' yourfile   #human readable

stat --printf='%W' yourfile   #seconds from Epoch , 0 if unknown

Note: this question is a duplicate of How to find creation date of file?. Also, make sure to read this question What file systems on Linux store the creation time?.

回答6:

Yup - stat(): http://manpages.ubuntu.com/manpages/hardy/man2/stat.2.html

回答7:

guys i just finished writing this script this script to find the creation date of a file using perl:

use File::stat;
if (  scalar( @ARGV ) == 0 ) {
 die("type  a file  name  ex:perl filestat.pl <filename>");    
}
my $filename =  $ARGV[0] ;
my @info = stat($filename);
print "Creation time :",scalar localtime stat($filename)->ctime;
print "\n";