Using the "du" command with a file-list [SOLVED]

Linux Tips & Tricks
1

As part of a backup script I want to find the total GB of a list of files to be backed up to see if the supplied USB stick is big enough.
The ideal command is du, for example:
keith@dt05:~$ du -sch Documents Desktop Pictures
2.4G Documents
73M Desktop
1.9G Pictures
4.4G total
keith@dt05:~$

Better still, du has an option to read the file list from a file:
–files0-from=
but the listed file/directory names must be NUL-terminated, and this is where I have become stuck.

A web search indicates “\0” as a null character but adding printf “\0” after a name when creating the file-list does not work, and I’ve tried many other variations offered on the web.
I would be grateful if anyone can suggest a way of listing files/directories in a file so that du will read it.

2

Solved!

Example:
keith@dt05:~$ more .bin/backup_file_list
Desktop
Documents
Dropbox
Music
Pictures
Programming
Radio
.fonts
.bin
keith@dt05:~$ readarray -t list < .bin/backup_file_list
keith@dt05:~$ du -sc ${list[@]} (NB ignore the "" used to display the “at” symbol)
74596 Desktop
2463444 Documents
142148 Dropbox
6730260 Music
1981068 Pictures
1484 Programming
36 Radio
224 .fonts
708 .bin
11393968 total
keith@dt05:~$

3

Easier still:

keith@dt05:~$ echo $(du -c $(cat .bin/backup_file_list) | tail -1 | cut -f 1)
11393972
keith@dt05:~$

This hasn’t solved the more elegant method of using the du command option –files0-from= but it does the job.