Copying a type of file, in specific directories, to another directory - linux

Question

I have a .txt file that contains a list of directories. I want to make a script that goes through this .txt file, copies anything in the directory thats listed of a certain file type, to another directory.
I've never done this with directories, only files.
How can i edit this simple script to work for reading a directory list, looking for a .csv file, and copy it to another directory?
cat filenames.list | \
while read FILENAME
do
find . -name "$FILENAME" -exec cp '{}' new_dir\;
done

Answer 1

for DIRNAME in $(dirname.list); do find $DIRNAME -type f -name "*.csv" -exec cp \{} dest \; ; done;
sorry, in my first answer i didnt understand what you asking for.
The first line of code, simply, take a dirname entry in your directory list as a path and search in it for each file which end with ".csv" extension; then copy it inside the destination you want.
But you could do with less code:
for DIRNAME in $(dirname.list); do cp $DIRNAME/*.csv dest ; done

Answer 2

Despite the filename of the list filenames.list, let me assume the file contains the list of directory names, not filenames. Then would you please try:
while IFS= read -r dir; do
find "$dir" -type f -name "*.mp3" -exec cp -p -- {} new_dir \;
done < filenames.list
The find command searches in "$dir" for files which have an extension .mp3 then copies them to the new_dir.
The script above does not care the duplication of the filenames. If you want to keep the original directory tree and/or need a countermeasure for the duplication of the filenames, please let me know.

Answer 3

Using find inside a while loop works but find will run on each line of the file, another alternative is to save the list in an array, that way find can search on the directories in the list in one search.
If you have bash4+ you can use mapfile.
mapfile -t directories < filenames.list
If you're stuck at bash3.
directories=()
while IFS= read -r line; do
directories+=("$lines")
done < filenames.list
Now if you're just after one file type like files ending in *.csv.
find "${directories[#]}" -type f -name '*.csv' -exec sh -c 'cp -v -- "$#" /newdirectory' _ {} +
If you have multiple file type to match and multiple directories to copy the files.
while IFS= read -r -d '' file; do
case $file in
*.csv) cp -v -- "$file" /foodirectory;; ##: csv file copy to foodirectory
*.mp3) cp -v -- "$file" /bardirectory;; ##: mp3 file copy to bardirectory
*.avi) cp -v -- "$file" /bazdirectory;; ##: avi file copy to bazdirectory
esac
done < <(find "${directories[#]}" -type f -print0)
find's print0 will work with read's -d '' when dealing with files with white spaces and newlines. see How can I find and deal with file names containing newlines, spaces or both?
The -- is there so if you have a problematic filename that starts with a dash - cp will not interpret it as an option.

Answer 4

Given find ability to process multiple folder, and assuming goal is to 'flatten' all csv files into a single destination, consider the following.
Note that it assumes folder names do not have special characters (including spaces, tabs, new lines, etc).
As a side benefit, it will minimize the number of 'cp' calls, making the process efficient across large number of files/folders.
find $(<filename.list) -name '*.csv' | xargs cp -t DESTINATION/
For the more complex case, where folder names/file name can be anything (including space, '*', etc.), consider using NUL separator (-print0 and -0).
xargs -I{} -t find '{}' -name '*.csv' <dd -print0 | xargs -0 -I{} -t cp -t new/ '{}'
Which will fork multiple find and multiple cp.