[SOLVED] Help with bash scripting

jim.thornton · 04-25-2012, 01:29 PM

I'm writing a script to copy all files within a directory that start with A-L a-l or 0-9 to one destinations and all files starting is m-z M-Z to another destination.

I got it working with the following commands:

Code:

RUNAL="cp -R {} /destination/directory/a-l"

find source_parent_dir -type d -regex "/source/parent/directory/[a-lA-L0-9].*" -exec "$RUNAL" \;

This works perfectly. However I then want to delete the files that were copied. Originally I was running the find command once to copy and then again to delete the directories/files. The problem is that I'm going to set this up on a cron. In the unlikely situation the files copy, then in the time of when the copying starts to when the copying finishes a new files is saved to the directory then the second find command would delete a file that wasn't copied.

I then came up with the idea to run the -exec command with && and a rm -rf:

Code:

RUNAL="cp -R {} /destination/directory/a-l && rm -rf {}"

find source_parent_dir -type d -regex "/source/parent/directory/[a-lA-L0-9].*" -exec "$RUNAL" \;

The weird thing is when I run the cp && rm command by itself in the shell it works. When I add it to the -exec parameter it doesn't work.

Now my idea is to run the find command, save the results into an array, then process the array and copy the files and then process the array and delete the files.

could anyone here please tell me how to save the results of the find command in an array. This is what I've done but it doesn't work:

Code:

declare -a files_found

find /source/parent/directory -maxdepth 1 -type d -regex "^/source/parent/directory/[a-l-A-L0-9].*" -exec array[${#files_found[*]} "{}" \;

suicidaleggroll · 04-25-2012, 01:38 PM

Why not just change your first script to move instead of copy?

grail · 04-25-2012, 01:39 PM

Maybe it would be better to pipe the data into a loop and then process the files (or should we say directories seeing the type -d switch) to be copied and then delete them.
Something like:

Code:

while read -r dir
do
    cp -R "$dir" /destination/directory/a-l && rm -rf "$dir"
done< <(find /source/parent/directory -maxdepth 1 -type d -regex "^/source/parent/directory/[a-l-A-L0-9].*")

jim.thornton · 04-25-2012, 01:40 PM

suicidaleggroll: Unfortunately you can't use the mv command when there are directories involved and you are moving from one device to another.

suicidaleggroll · 04-25-2012, 01:53 PM

Quote:

Originally Posted by jim.thornton

suicidaleggroll: Unfortunately you can't use the mv command when there are directories involved and you are moving from one device to another.

Why not? Here is me moving a directory with two files onto and off of a USB flash drive:

Code:

$ ls
$ mkdir testdir
$ touch testdir/testfile1
$ touch testdir/testfile2
$ mv testdir ~/
$ ls
$ mv ~/testdir .
$ ls
testdir
$ls testdir
testfile1  testfile2

Barring that, I would put it inside a loop like grail suggested

jim.thornton · 04-25-2012, 01:56 PM

suicidaleggroll: All I know is I am getting an error message when using mv and when researching that error message it seems to be a limitation with mv.

jim.thornton · 04-25-2012, 02:02 PM

grail: Thank you, that worked perfectly and is alot easier than what I was doing.

Could you please explain a few things for me:

1. What does the -r flag do on the while read -r dir?

2. done< <(command)
- what exactly is < < ?
- does there have to be a space between them
- can I use any command in there that outputs something?

grail · 04-25-2012, 02:32 PM

Quote:

1. What does the -r flag do on the while read -r dir?

I find help is easier to use than man here:

Code:

-r		do not allow backslashes to escape any characters

Quote:

2. done< <(command)
a what exactly is < < ?
b does there have to be a space between them
c can I use any command in there that outputs something?

a) Process substitution - http://mywiki.wooledge.org/ProcessSubstitution

b) Yes (see link)

c) Yes (see link)