A file system structure in which to store computer files.

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17
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2answers
25k views

rsync compare directories?

Is it possible to compare two directories with rsync and only print the differences? There's a dry-run option, but when I increase verbosity to a certain level, every file compared is shown. ls -alR ...
17
votes
4answers
22k views

How to copy-merge two directories? [duplicate]

I have two directories images and images2 with this structure in Linux: /images/ad /images/fe /images/foo ... and other 4000 folders and the other is like: /images2/ad /images2/fe ...
17
votes
3answers
1k views

Simple way to see the content of directories in Linux/UNIX file systems

In the past, I learned that in Linux/UNIX file systems, directories are just files, which contain the filenames and inode numbers of the files inside the directory. Is there a simple way to see the ...
17
votes
2answers
4k views

games directory?

On a standard filesystem, we have: /usr/games /usr/lib/games /usr/local/games /usr/share/games /var/games /var/lib/games Is this a joke, or is there some history behind this? What is it for? Why do ...
16
votes
3answers
1k views

Can I make a public directory under a private directory?

I have a personal folder /a/b on the server with permission 700. I don't want others to list the contents in /a/b. The owner of /a is root. Now I need to open the full authorities of directory /a/b/c ...
16
votes
3answers
15k views

How can I move files by type recursively from a directory and its sub-directories to another directory?

What would be a good way to move a file type from a directory and all of its sub-directories? Like "move all *.ogg in /thisdir recursively to /somedir". I tried a couple of things; my best effort was ...
15
votes
4answers
3k views

Best method to collect a random sample from a collection of files

Suppose there is a directory holding 300 data files. I want to randomly select 200 of those files and move them into another directory. Is there a way to do that under Unix/Linux?
14
votes
5answers
10k views

How can I copy a file and create the target directories at the same time?

I want to cp aaa/deep/sea/blob.psd to bbb/deep/sea/blob.psd How do I do the copy if the deep and sea directories don't exist under bbb so that the copy both creates the directories that are needed ...
14
votes
5answers
2k views

How is a directory a “special type of file”?

I am reading this Unix tutorial and came across this quote... We should note here that a directory is merely a special type of file. ...but no explanation or details are provided. How is a ...
14
votes
7answers
595 views

Compact bash prompt when using a directory tree / filename

In a system with Ubuntu 14.04 and bash, I have the PS1 variable ending with the following contents: \u@\h:\w\$ so that the prompt appears as user@machinename:/home/mydirectory$ Sometimes, ...
14
votes
7answers
51k views

Using sftp to Transfer a Directory?

When I try to use sftp to transfer a directory containing files, I get an error message: skipping non-regular file directory_name The directory contains a couple of files and two subdirectories. ...
13
votes
4answers
4k views

How does one atomically change a symlink to a directory in busybox?

I am trying to (as close as possibly) atomically change a symlink. I've tried: ln -sf other_dir existing_symlink That just put the new symlink in the directory that existing_symlink pointed to. ln ...
13
votes
4answers
2k views

Should I include a trailing slash / in a symlink to a directory?

Symlinking to a directory gives to different results with ls -l depending on whether I ln -s dir or ln -s dir/. But what's the actual difference, and which one should I prefer why?
13
votes
5answers
361 views

How can I find the first missing directory in a long path?

Imagine I have a path that doesn't exist: $ ls /foo/bar/baz/hello/world ls: cannot access /foo/bar/baz/hello/world: No such file or directory But let's say /foo/bar does exist. Is there a quick way ...
13
votes
3answers
11k views

Simplest way to password protect a directory and its contents without having to create new files?

I would like to password protect or encrypt a directory and all the files within it (for the whole directory tree below it). I do not want to bother the whole home directory, I want a specific ...
13
votes
4answers
13k views

How can I force unzip / zip not to create a subdirectory when I extract it?

Depending on how a zip file is created, sometimes it will extract all of the files directly, and sometimes it will extract the files into a subdirectory. If the latter is true, how can I force the ...
12
votes
3answers
51k views

How can I delete all files with a particular extension in a particular folder?

If I set the current/working directory (navigating to it using cd) to some particular directory and then type: rm *.xvg What will this command do? Is it true that the above command will only ...
12
votes
4answers
5k views

How to run a command when a directory's contents are updated?

There is a directory A whose contents are changed frequently by other people. I have made a personal directory B where I keep all the files that have ever been in A. Currently I just occasionally ...
12
votes
4answers
6k views

Recursively iterate through files in a directory

Recursively iterating through files in a directory can easily be done by: find . -type f -exec bar {} \; However, the above does not work for more complex things, where a lot of conditional ...
12
votes
3answers
5k views

Stay at same working directory when changing to sudo

When working on the command line, I often change to sudo using sudo -i. However, my working directory changes automatically to /root. I never want to go there; I want to stay where I was! How can I ...
12
votes
1answer
2k views

How to find all the links to a directory

When I stat a directory I get a listing that tell me there are 5 links to the directory. stat dir My question is how do I get information (names and locations) to all these 5 links?
12
votes
1answer
986 views

Tab completion of “../” in zsh

One noob question from a new zsh user: In bash, I can use tab-completion to move one directory up and descend down again another path. For example, suppose I'm in $HOME/folder1, and I want to cd to ...
12
votes
1answer
219 views

How to log all the events performed on directory?

How can I log all the events performed on a particular directory? I want to log the entry of each directory modified within some time duration. I am using find . -type d -mmin -5 command. In ...
11
votes
4answers
9k views

symbolic link to a directory and relative path

I've created symlink with absolute path to the directory (Blink) and have for example following tree: $ ls -l /tmp/A total 0 lrwxrwxrwx 1 root root 6 Apr 3 12:27 Blink -> /tmp/B -rw-r--r-- 1 root ...
11
votes
2answers
7k views

Why can't I have a folder and a file with the same name?

I've never had this problem before, but for some reason, I can't rename my folder to packages/. This is the structure: root - packages_old/ - packages When I try to rename the folder with ...
11
votes
4answers
2k views

How do I choose specific files in a different directory using bash?

I want to list (or delete, or do some other operation) on certain files in a directory, like this: $ ls /opt/somedir/ aa bb cc aa.txt bb.txt cc.txt $ ls /opt/somedir/(aa|bb|cc) ## pseudo-bash ...
11
votes
2answers
8k views

How to make tree output only directories?

150 directories I can handle but 900 files is too many for a review. I've no manual entry for tree so maybe I can ask you if you know how to output only directories since files get too detailed? . ...
11
votes
5answers
3k views

How do you check if a file exists within awk? [-d 'filename'] failing

I'm trying to generate a list of users who have a home directory set which does not exist. It seems I should be able to do this with awk, but something is wrong with my syntax. It keeps telling me ...
11
votes
3answers
2k views

Why are some files and folders hidden?

I can understand the rationale of hiding files and folders in the /home/user directory to prevent users from messing around with things. However, I do not see how the same rationale can be applied to ...
11
votes
1answer
2k views

What is the difference between 'ls' and 'ls -l' when I don't have execute permission on that directory?

I created a directory called folder and took away execute permission. $ mkdir folder $ touch folder/innerFile $ mkdir folder/innerFolder $ chmod -x folder Now if I do $ ls folder it outputs a ...
11
votes
3answers
6k views

find with -execdir

I run a find with -execdir both I don't get the results I was expecting. SSCCE below: mkdir -p a/b/c find . -type d -execdir touch foo \; $ tree a a ├── b │   ├── c │   └── foo └── foo Directory c ...
11
votes
1answer
3k views

Why is this empty directory 3.5MB?

I've just read this question: What does size of a directory mean in output of 'ls -l' command? ...which doesn't quite answer my question. Basically, I'm moving files onto a NAS. The folders ...
10
votes
5answers
18k views

Creating numerous directories using mkdir

I would like to create many directories using mkdir. Each directory name will consist of a prefix (a string) and an index (an integer). Suppose that I would like the prefix to be "s" and the indices ...
10
votes
3answers
1k views

Why is it rm -rf and not rmdir -rf

I've always been curious why the command for deleting everything in a directory is rm -rf. Why aren't there flags to do the same thing with rmdir? Wouldn't it be more intuitive to use rmdir for ...
10
votes
3answers
4k views

what is wild card to select all directories in a directory

i want to set sticky bit for all directories in a directory excluding files. is there any wild card to do this? #sudo chmod g+s /var/www/<WILD_CARD_FOR_ALL_DIRECTORIES>
10
votes
3answers
4k views

How to switch to the directory listing from file view in vim?

I have opened a dir vim some/dir. I can navigate within the tree, yet once I opened a file I wonder, how do I close the file view in order to go back to the directory listing to navigate to another ...
10
votes
6answers
2k views

Best way run a command on each file in a directory tree

There appear be a number of ways to do this including loops in shell script, find and xargs. Which of these is best, and which is most portable?
10
votes
2answers
464 views

Is a directory removed when its number of hard links becomes 0?

Is a directory removed when its number of hard links becomes 0? A directory always has at least 2 as its number of hard links, because of .. When rm -r a directory, does it decrease the number of ...
10
votes
6answers
884 views

File systems vs partitions vs directories

I am new to Linux so pardon me for the possible confusion you may encounter in this question. From what I understand, filesystem specifies how a partition stores/manages file, with standards such as ...
10
votes
2answers
7k views

Why does a new directory have a hard link count of 2 before anything is added to it?

Say I just create directory newDirectory and then I do ls -ld command. I see that the number of hard links is 2. What exactly makes the hard link 2 from the start? Also is the number of subdirectories ...
10
votes
4answers
3k views

set read and write permissions to folder and all its parent directories

I need to set read and write permissions for root user to directory subfolderN and all its parent folders till root. I can do it by hands: $ sudo chmod +rx /root/subfolder1/subfolder2/subfolderN $ ...
10
votes
3answers
1k views

Lowercasing all directories under a directory

I want to lowercase every directories' name under a directory. With which commands can I do that?
10
votes
2answers
155 views

Are there any filesystems for which `ln -d` succeeds?

From the manpage for ln: -d, -F, --directory allow the superuser to attempt to hard link directories (note: will probably fail due to system restrictions, even for the superuser) Are there any ...
10
votes
3answers
1k views

Boot into a chroot?

I have Linux (Debian Jessie) installed on a hard drive. Drive - sda1, ext4fs, and sda2 - swap I have a /chroot folder. There is installed another system, in /chroot folder. Question: How to tell ...
9
votes
5answers
6k views

pv for directory copy

I need to copy a very large directory (talking in terabytes here) and want to monitor the progress. I found that pv is a nice utility, but how can I use it for copying directories recursively? (pv ...
9
votes
6answers
4k views

Remove empty directory trees (removing as many directories as possible but no files)

Suppose I have a dir tree like this: ROOTDIR └--SUBDIR1 └----SUBDIR2 └----SUBDIR3 I am looking for a command such that when I input: $ [unknown command] ROOTDIR The whole ...
9
votes
4answers
7k views

How are directories implemented in Unix filesystems?

My question is how directories are implemented? I can believe a data structure like a variable e.g. table, array or similar. Since UNIX is Open Source I can look in the source what the program does ...
9
votes
1answer
4k views

how to view a directory's permission

What is the command with which you can directly view the permission bits of a directory?
9
votes
2answers
450 views

How to spoof/mock a directory used by a binary application as another directory?

Suppose there's a binary application that always writes its data to /tmp. How could I spoof/mock /tmp for the sake of this binary as some other directory (e.g. home/tmp)? Let's assume I have no ...
9
votes
4answers
12k views

How do I change folder timestamps recursively to the newest file?

I was wondering if anyone knows how to change the timestamps of folders recursively based on the latest timestamp found of the files in that folder. So for example: ...