Is there a way to change the date when a file was modified/created (which is shown in Nautilus or with the ls -l command)? Ideally I am looking for a command which can change the date/time stamps of a whole bunch of files to a certain amount of time earlier or later (e.g. +8 hours or -4 days etc.).
6 Answers
As long as you are the owner of the file (or root), you can change the modification time of a file using the touch
command:
touch filename
By default this will set the file's modification time to the current time, but there are a number of flags, such as the -d
flag to pick a particular date. So for example, to set a file as being modified two hours before the present, you could use the following:
touch -d "2 hours ago" filename
If you want to modify the file relative to its existing modification time instead, the following should do the trick:
touch -d "$(date -R -r filename) - 2 hours" filename
If you want to modify a large number of files, you could use the following:
find DIRECTORY -print | while read filename; do
# do whatever you want with the file
touch -d "$(date -R -r "$filename") - 2 hours" "$filename"
done
You can change the arguments to find
to select only the files you are interested in. If you only want to update the file modification times relative to the present time, you can simplify this to:
find DIRECTORY -exec touch -d "2 hours ago" {} +
This form isn't possible with the file time relative version because it uses the shell to form the arguments to touch
.
As far as the creation time goes, most Linux file systems do not keep track of this value. There is a ctime
associated with files, but it tracks when the file metadata was last changed. If the file never has its permissions changed, it might happen to hold the creation time, but this is a coincidence. Explicitly changing the file modification time counts as a metadata change, so will also have the side effect of updating the ctime
.
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6To mention the simpler case when all files are in the same folder:
touch -d "2 hours ago" /path/*.txt
, for example.– enzotibSep 22, 2011 at 7:05 -
4I'd also add that changing the
ctime
is not possible in any standard way.– arrangeSep 22, 2011 at 7:40 -
2The information about
ctime
as a metadata change time is from POSIX. I don't know if the shell fragments in my answer would work with strict POSIX shell utilities. But they definitely work on Ubuntu, which is the context for answers on this site. Sep 15, 2015 at 22:27 -
2
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5
Easiest way - accessed and modified will be the same:
touch -a -m -t 201512180130.09 fileName.ext
Where:
-a = accessed
-m = modified
-t = timestamp - use [[CC]YY]MMDDhhmm[.ss] time format
If you wish to use NOW
just drop the -t
and the timestamp.
To verify they are all the same:
stat fileName.ext
See: man touch
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1I tried to verify it using stat, but neither of the
touch
flags lead to a correct result. Modification date is adjusted, but changed and accessed date are actually changed to NOW– xerufMar 19, 2018 at 20:51 -
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1@Revious , Xerus What's the difference between the
changed
time and themodified
timestamps?– ijosephMay 26, 2019 at 20:49 -
@ljoseph, take a look here:
https://www.howtogeek.com/517098/linux-file-timestamps-explained-atime-mtime-and-ctime/#:~:text=%E2%80%9CModified%E2%80%9D%20means%20something%20inside%20the,will%20update%20the%20changed%20timestamp.
– JadeyeMar 7, 2021 at 10:52 -
2Using "-a" and "-m" together is probably unnecessary, "-a" is "change only the access time", and "-m" is "change only the modification time". If you want to update both, you don't need to use any option. Oct 13, 2021 at 8:57
Thanks for the help. This worked for me:
In the terminal go to the directory for date-edit. Then type:
find -print | while read filename; do
# do whatever you want with the file
touch -t 201203101513 "$filename"
done
You wil see a ">" after you hit enter, exept for the last time -> "done".
Note: You may want to change "201203101513"
"201203101513" = is the date you want for all the files in this directory.
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1Webpage is no longer, albeit it is 6 years later. Nonetheless, this is the answer I was looking for. For those who want to include seconds in their time, use
.ss
where ss is the number of seconds. (Note: this does not seem to control sub-second timings such as nanoseconds or milliseconds, which for me just appeared as zeros; however, this difference was permissible for my use-case.) Dec 9, 2018 at 19:32
Touch can reference a file's date all by itself, no need to call date
or use command substitution. Here's a bit from touch's info page:
`-r FILE' `--reference=FILE'
Use the times of the reference FILE instead of the current time.
If this option is combined with the `--date=TIME' (`-d TIME')
option, the reference FILE's time is the origin for any relative
TIMEs given, but is otherwise ignored. For example, `-r foo -d
'-5 seconds'' specifies a time stamp equal to five seconds before
the corresponding time stamp for `foo'. If FILE is a symbolic
link, the reference timestamp is taken from the target of the
symlink, unless `-h' was also in effect.
For example, to add 8 hours to a file's date (filename of file
quoted just in case of spaces, etc):
touch -r "file" -d '+8 hour' "file"
Using a loop over all files in the current dir:
for i in *; do touch -r "$i" -d '+8 hour' "$i"; done
I've heard that using a *
and letting for
pick the filenames itself is safer, but using find -print0 | xargs -0 touch ...
should handle most crazy characters like newlines, spaces, quotes, backslashes in a filename. (PS. try not to use crazy characters in filenames in the first place).
For example, to find all files in thatdir
whose filenames start with an s
, and add one day to those file's modified timestamp, use:
find thatdir -name "s*" -print0 | xargs -0 -I '{}' touch -r '{}' -d '+1 day' '{}'
This little script at least works for me:
#!/bin/bash
# find specific files
files=$(find . -type f -name '*.JPG')
# use newline as file separator (handle spaces in filenames)
IFS=$'\n'
for f in ${files}
do
# read file modification date using stat as seconds
# adjust date backwards (1 month) using date and print in correct format
# change file time using touch
touch -t $(date -v -1m -r $(stat -f %m "${f}") +%Y%m%d%H%M.%S) "${f}"
done
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3Adjusting the date of images based on meta info in the image would be pretty useful. ImageMagick's identify can be used. e.g. 'identify -verbose <image> |grep -i date', 'identify -format %[exif:DateTime] <image>' might show '2015:01:08 10:19:10' (not all images have exif data). This works(using sed to convert date to format touch can handle): 'touch -d $(identify -format %[exif:DateTime] $f|sed -r 's/:/-/;s/:/-/;') $f'– gaoitheMay 24, 2016 at 11:30
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1
It's been a long time since I wrote any kind of Unix program, but I accidentally set the year incorrectly on a bunch of Christmas photos, and I knew if I didn't change the date from 2015 to 2014 it would be a problem later on.
Maybe, this is an easy task, but I didn't find any simple way to do it.
I modified a script I found here, which originally was used to modify the date by minus one month.
Here's the original script:
#!/bin/bash
# find specific files
files=$(find . -type f -name '*.JPG')
# use newline as file separator (handle spaces in filenames)
IFS=$'\n'
for f in ${files}
do
# read file modification date using stat as seconds
# adjust date backwards (1 month) using date and print in correct format
# change file time using touch
touch -t $(date -v -1m -r $(stat -f %m "${f}") +%Y%m%d%H%M.%S) "${f}"
done
Here's my modified script that forced the date to the year "2014":
#!/bin/bash
# find specific files
#files=$(find . -type f -name '*.JPG')
# use newline as file separator (handle spaces in filenames)
IFS=$'\n'
for f in $*
do
# read file modification date using stat as seconds
# adjust date backwards (1 month) using date and print in correct format
# change file time using touch
touch -t $(date -v +1y -r $(stat -f %m "${f}") +2014%m%d%H%M.%S) "${f}"
done
I now realize I could have done a more generic version:
#!/bin/bash
# find specific files
#files=$(find . -type f -name '*.JPG')
# use newline as file separator (handle spaces in filenames)
IFS=$'\n'
for f in $*
do
# read file modification date using stat as seconds
# adjust date backwards (1 month) using date and print in correct format
# change file time using touch (+1y adds a year "-1y" subtracts a year)
# Below line subtracts a year
touch -t $(date -v -1y -r $(stat -f %m "${f}") +%Y%m%d%H%M.%S) "${f}"
# Below line adds a year
# touch -t $(date -v +1y -r $(stat -f %m "${f}") +%Y%m%d%H%M.%S) "${f}"
done
To use this file you would need to write it and
chmod +x fn
to execute:
./fn files-to-change
fn=your-file-name-that-is-your-command
Example
./fn *.JPG
will change the date by minus one year in the directory where you are.
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2Same as above comment. Most .jpg files will have date embedded in meta data aded by camera. This works(using sed to convert date to format touch can handle): 'touch -d $(identify -format %[exif:DateTime] $f|sed -r 's/:/-/;s/:/-/;') $f'– gaoitheMay 25, 2016 at 9:49