Append human readable timestamp of last edit to filename

Question

I would like to add the time of the last change to the file to its filename using the bash.

For example this output of ls -la:

 -rw-rw-r-- 1 beginner beginner 5382 Dec  1 17:18 B_F1-1.xml

should become

 -rw-rw-r-- 1 beginner beginner 5382 Dec  1 17:18 B_F1-1_20141201T1718.xml

How could I do this to all files in .?

Answer 1

You can try something like:

EXT=${FILE#*.}
NAME=${FILE%%.*}

mv "$FILE" "$NAME$(date --reference "$FILE" '+%Y%m%dT%H%M').$EXT"

in a script, if your date supports --reference, which picks up the last modification date of the reference file.

Answer 2

I think this could work:

for i in *; do 
   fileTime=$(stat -c %Y "$i");  #Get last modification (since EPOCH)
   formatDate=$(date +%Y%m%dT%H%m -d @"$fileTime"); #Get time in format YYYYMMDDTHHmm
   mv "${i%%.*}"_"$formatDate"."${i#*.}"; #Appends "formatDate" before extension
done

Regards.

Answer 3

This can all be done as a oneliner.

for i in *.* ; do mv "$i" "${i%.*}_$(date --reference "$i" +%Y%m%dT%H%M).${i##*.}"; done

For a literal timestamp, i.e., seconds since the epoch, you can just use:

for i in *.* ; do mv "$i" "${i%.*}_$(date --reference "$i" +%s).${i##*.}"; done

This has a safety check to only operate on files whose names contain dots; it correctly handles files with spaces in the names; and it assumes (as would usually be the case) that the LAST dot separated field is the extension, rather than the FIRST dot separated field being the filename and the rest being an extension.

Credit to muru for the --reference bit; I didn't know about that option.