read creation date from file name and change - batch

Question

I have files that are named like "clip-2014-01-31 18;50;15.mp4", i.e. "clip-YYYY-MM-DD hh;mm;ss.mp4".

How can I set the creation date and time according to how it is specified in the file name for all 2000 files I have in a folder. I know the command touch -t changes the creation date, but I do not know how to extract the date/time information from the file name and put this into a command so this is done automatically for all files.

Answer 1

You're lucky because the numbers in your file names are in just the order touch -t needs.

This command in the terminal will work. You just need to make sure your working directory is set to the folder you want to do:

for f in *; do
    t=$(echo $f | sed -E 's/([A-z]*-)|([ ,;])|(\..*)//g' | sed -E 's/(.*)(..)/\1.\2/')
    touch -t $t "$f"
done

To break it down:

for f in * sets the variable f to the name of each file in the directory, in turn.

do puts everything until the done into the for loop.

t=$(…) sets the variable t to the output of the commands in the parentheses.

The first sed command matches any letters before a - symbol, the - ; and the space symbols, and the file extension, and deletes them.

The second sed command inserts a period between the mm and ss values, as touch requires.

touch -t $t $f changes the file modification and creation times to the value of t on the file f.

Tested on some dummy files with whatever version of sed ships with Mavericks.