Is there anything special about directories which start with a dot . in Linux (Ubuntu), such as ~/.vim?
Thanks.
Files and directories whose names begin with a dot (.) by default are not displayed in directory listings by the standard command ls. Therefore, they are traditionally used to store settings, preferences, etc.. Directory ~/.vim in particular surely contains personal preferences and settings for the text editor vim.
There are also two special directory names in this class: the directory named simply . is an alias for the same directory in which it appears (a self reference), and the directory named .. refers to the parent directory of ..
Many graphical file browsers ignore the convention of hiding file names beginning with a ., so it is not necessarily correct any longer to call these files "hidden". Nevertheless, that terminology persists.
In UNIX-like environments, a filename preceded by a dot indicates a hidden file. It's mainly a mechanism to decrease clutter in directory listings. You can get a listing of hidden files by passing the -a parameter to ls
Those are hidden. You'd need to apply extra effort to see them.
Related
With more and more programs installed on my computer, I am tired of seeing lots of dotfiles while I have to access them often. For some reason I won't hide dotfiles when browsing files. Is there a way to move them to a better place I want them to stay (e.g. ~/.config/$PROGCONF) without affecting programs while running?
Symlinks still leave file symbols, which is far from my expectation. I expect that operations like listdirs() won't show the files while opening them uses a redirection.
"For some reason it won't hide dotfiles when browsing files.":
That depends on the file manager you use. nautilus hides it by default and most file managers have an option to "show/hide hidden files". The ls command by default omits out hidden files (files starting with a dot). It lists all files with the option -a.
"Is there a way to move them to a better place":
Programs which have support for "XDG user directories" can store their config files in `~/.config/$PROGRAM_NAME/. If the program doesn't support that and expects the config file to be present in the home directory, there is little you can do (Maybe you can give us a list of what programs' config files you want to move). The process differs for each program.
Let me give an example with vim. Its config file is ~/.vimrc. Lets say you move the file to ~/.config/vim/.vimrc. You can make vim read the file by launching vim using the following command.
vim -u ~/.config/vim/.vimrc
You can modify the .desktop entry or create a new shell script to launch vim using the above command and put it inside /usr/local/bin/ or create shell functions / aliases. You can read more about changing vim's config file location in this SO question.
This arch wiki article has application specific information.
"without affecting programs while running":
It depends on a few factors namely the file system used, the program we are dealing with and so on.
Generally, deleting / moving files only unlinks the file name from an inode and programs read / write files using inodes. Read more here. And most programs read the config file at the start, load the values into memory. They rarely read the config files again. So, if you move your config file while the program is running (assuming the program supports config in both places), you won't see a difference until the program is restarted.
"I expect that operations like listdirs() won't show the files"
I am assuming you are talking about os.listdir() in python. If files are present, os.listdir() will list them, there is little you can change about that. But you can write custom functions to omit out the hidden files from being listed.
This SO question can help with that.
In no way do i think i'm an adequate unix administrator but i'm learning. I "cd" into a specific directory and it appears to be empty after i do a "ls". But when i "ll" it says this:
/integration/import$ ll
total 184
What is this total 184? And how do i see these text files. I've never seen anything like this before. super confusing.
My co-worker had originally said this: in the imports folder find the text file containing this order and move it out of the folder/queue.
The below should list the hidden files as well. Usually, hidden files are the one starting with a dot. e.g. .mail or so.
ls -latr /integration/import/
"Hidden files" are files with name prefix ., e.g. /home/pxf/.xxx.
.xxx is an invisible file and 'ls' will not list it.
Is there a concept of "hidden file" On Linux Kernel? I mean that are there difference between "regular files" and "hidden files"?
Or just it's a conventional rule that a file with prefix . will not be shown by default such as ls. (except with -a option)?
See Wikipedia: Hidden file and hidden directory
They are not a security mechanism because access is not restricted - usually the intent is simply not "clutter" the display of the contents of a directory listing with files the user did not directly create.
This is just a convenient convention that application may or may not observe. The invisibility of these files is not enforced by the kernel.
The ls -ai command shows that . and .. have their inodes the same as the current directory and parent directory, respectively.
What exactly are . and ..?
Are they real files or even hard links? But as I have known, it's not allowed to create a hard link to a directory.
. represents the directory you are in and .. represents the parent directory.
From the dot definition:
This is a short string (i.e., sequence of characters) that is added to
the end of the base name (i.e., the main part of the name) of a file
or directory in order to indicate the type of file or directory.
On Unix-like operating systems every directory contains, as a minimum,
an object represented by a single dot and another represented by two
successive dots. The former refers to the directory itself and the
latter refers to its parent directory (i.e., the directory that
contains it). These items are automatically created in every
directory, as can be seen by using the ls command with its -a option
(which instructs it to show all of its contents, including hidden
items).
They are special name-inode maps which do count as hard-links (they do increase the link-count) though they aren't really hard-links, since, as you said, directories can't have hard-links. Read more here: Hard links and Unix file system nodes (inodes)
. represents the current directory that you are using and
.. represents the parent directory.
Example:
Suppose you are in the directory /etc/mysql and you wanted to move to the parent directory, i.e. /etc/. Then use cd..:
/etc/mysql> cd ..
And if you wanted to set the path of one file in the current directory bash file, use . with file name like this: ./filename
They are not hard links. You can more think of it like a shorthand for this directory (.) and parent of this directory (..).
Try to remove or rename . or ... Then you understand why it is not a hard link.
I have a system fedora 15 with xfce window manager.
I installed an inotify util to play with.
I want to control, what happens with my files during my work process.
There is a command which i use today for running inotify
inotifywait --fromfile ~/list.inotify
That command easy read a list of folders and files to read and to ignore.
There is my list (list.inotify)
/home/alex
#/home/alex/Torrnets/
#/home/alex/.pulse-cookie
So it should read my home folder and ignore Torrents folder and .pulse-cookie file.
It ignores Torrents as well. But it won't ignore a .pulse-cookie file.
Any solution for this ? (please don't post a solution to use pattern based ignore, i want to work with a file list with absolute path's)
$man inotify
#<file>
When watching a directory tree recursively, exclude the specified file from being watched. The file must be specified with a relative or absolute path according to whether a relative or absolute path is given for watched directories. If a specific
path is explicitly both included and excluded, it will always be watched.
Note: If you need to watch a directory or file whose name starts with #, give the absolute path.
--fromfile <file>
Read filenames to watch or exclude from a file, one filename per line. If filenames begin with # they are excluded as described above. If <file> is `-', filenames are read from standard input. Use this option if you need to watch too many files to
pass in as command line arguments.
If you don't specify a -e argument, inotifywait will call inotify_add_watch with IN_ALL_EVENTS, which causes events to occur for files inside watched directories - note that inotify(7) says:
When monitoring a directory, the events marked with an asterisk (*) above can occur for files in the directory, in which case
the name field in the returned inotify_event structure identifies the name of the file within the directory.
If you have a look at the inotifywait code in question, you'll see that it only watches (and checks the exclude list against) directories. It would perhaps be a bit more user friendly if you were warned when specifying an exclusion that is not a directory or one that is never used, but that's the way it currently it is.