2
votes
2answers
53 views

Is reading a file on UNIX faster than writing a file?

Sorry for the sheer simplicity of this question. A rather obtuse performance bottleneck has boiled down to this very small query. I have done some empirical analysis and I think I might be getting ...
1
vote
0answers
21 views

How can I unveal files on my external hard drive?

I copied a big folder (around 110 GB) from my (Mac 10.7.5) computer onto a hard drive (exFAT). It took quite some time and afterwards I even checked that the files were actually there. After more ...
2
votes
1answer
43 views

What is advisory locking on files that Unix systems typically employs?

I read that Unix like system typically use advisory locking for file IO vs mandatory locking used by Microsoft OS's. If I understood correctly in mandatory locking file lock is enforced by the OS ...
5
votes
4answers
237 views

Ways to organize and access frequently visited directories and files?

In my Ubuntu, I have added some frequented directories to the bookmarks of Nautilus, for visiting them quicker. Nautilus can consume a lot of memory, when it has been kept open for long and there ...
11
votes
1answer
426 views

How is file owner and group remembered for an external drive?

I formatted an external hard drive with an ext4 partition and subsequently mounted it. So that I could use the new partition, I did: sudo chown me:me /mount/directory to change the file owner and ...
0
votes
1answer
34 views

setfacl remove all write access

I want to remove all write access to files & directories for any user or group while preserving other permissions. Is this possible?
1
vote
1answer
63 views

How to install a .bin file that gives the error that it needs more space in /tmp?

Here is the error: ~]$ ./jdev_suite_121200_linux64.bin 0%....................................................................................................100% Not enough disk space in dir ...
3
votes
1answer
54 views

Does du or df perform caching?

I was wondering if there is any caching done with these utilities. I assume not, but not positive. Are there any typical similar utilities that do use caching to speed up results on subsequent runs? ...
0
votes
0answers
48 views

Unable to make file system writtable no matter what

I have a flash card SanDisk of a camera which I plug in into my computer: $ lsblk mmcblk0 179:0 0 3.7G 1 disk └─mmcblk0p1 179:1 0 3.7G 1 part $ mount /dev/mmcblk0p1 on ...
2
votes
2answers
342 views

Unable to remove the files from an usb drive (neither by dd /dev/zero nor by rm -r)

I have a flash usb drive and up till now it has worked well. Recently I recorded iso to it using dd. Now I want to delete it. $ lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT ....... sdb ...
2
votes
1answer
235 views

Why do deleted files continually reappear?

I've been having a strange issue recently, where I would delete files from a location (i.e. Desktop), and then empty the Trash. However, a day or so later (I'm not sure exactly what triggers it), the ...
1
vote
1answer
113 views

File has bytes - appears to be empty

I'm having the following problem: Some text files (also some binary files) on my system are listed with the correct file size but when I open them, they appear empty. >ls -la -rw-rw-r-- 1 user ...
13
votes
2answers
444 views

Is that possible to integrate zip and tar.gz files as directory into the file system

I wonder if there is a way to integrate (it's a bit different from mounting, I think) compressed files as directories into the file system? E.g., one could download a compressed-file.tar.gz to his ...
2
votes
1answer
64 views

How to link the unlinked files?

When you rm a file it will call unlink(), and unlink() will remove the file from the Directory entry and its inode is freed. But, the actual content of the file is still in the disk. Is there any way ...
4
votes
3answers
290 views

Hidden Files&Directories in user's home directory [closed]

I am in my user's home directory, I do: ls -a Then it shows me large number of hidden files and directories in my user's directory. Which of them I am allowed to remove? Which ones are necessary ...
5
votes
1answer
451 views

Cannot delete broken symbolic link

I have a symbolic link formerly pointing to a Dropbox directory. I don't know what I did wrong, but apparently now it points to itself. hyper@mypi:/home/hyper/test$ ls -l total 1024 lrwxrwxrwx 1 ...
2
votes
1answer
39 views

Ignore file changes

I have a process, which generates a file with configuration data and then calls a subprocess with this data as parameter. I'd like to override the configuration data, which is passed. The problem is, ...
3
votes
0answers
71 views

How does fsnotify setting affect system performance?

Occasionally a software package I install complains that the default fsnotify setting is far too low for decent performance. Intellij IDEA or crashplan are two examples. They suggest using fsnotify ...
1
vote
2answers
65 views

Something like a symbolically linked file, but with change details attached?

Is there a file type or method for using files in which certain files look and behave like symbolically linked files, but contain extra meta information for changing the data when they are read? ...
3
votes
1answer
56 views

Where are information stored information about hard/soft links

Where does the *nix system store information about number of hard links to a specific inode? I can't find any information about that. Everywhere what a hard link is but rarely a bit more advanced ...
6
votes
5answers
836 views

How does one find out how many bits a file has in one command?

I know I can use ls -lat to find out how many bytes has a file and then multiply by 8 to find out how many bits. But is this possible in only one command line?
1
vote
1answer
102 views

Monitor file access count by user

I have written a script which is deployed just by putting it in a globally accessible location for all users. I want to log the usage of this script. Is there a way in Linux to find out how many ...
2
votes
1answer
507 views

How to Free Up Space in a Dynamically Growing qcow2 VM image?

This has happened to one of my VM's that's running CentOS under Proxmox. I copied about 40 GB of data into a VM. I then deleted that 40 GB data a day later. Now taking a backup of the same VM takes ...
1
vote
2answers
50 views

Machine keeps backups of files that I have already deleted

I recently found out that my machine keeps backups of files that I have already deleted. For example, a file called a.svg that I have deleted in the past, still exists in the directory it was deleted ...
2
votes
3answers
217 views

What command do I use to see the start and end block of a file in the file system?

Is there any command that will output the beginning and ending blocks of any file?
2
votes
2answers
91 views

What are the differences between split and rar?

I am used to raring files -- but I am looking for something faster. I see that there is a "split" command. How does this command compare to rar? What is are the differences between split and rar?
5
votes
2answers
1k views

Why are 666 the default file creation permissions?

As I've found out, when using umask, the highest permissions you can give to files are 666. Which is done by umask 0000. That's because of the default file creation permissions, which appear to be 666 ...
2
votes
1answer
363 views

Hang during 'touch' operation on NFS mount

I have two NFS clients mounted to an openfiler 2.99 NFS share at 192.0.2.3: 192.0.2.1 mounts 192.0.2.3:/mnt/nfs01/volnfs01/share01 with ...
5
votes
2answers
254 views

A virtual file containing the concatenation of other files

Is there a way of creating a filesystem object akin to this: mknod files p cat file1 file2 ... fileN > files but such that it can be seeked in, as if it were a regular file?
3
votes
3answers
2k views

How can I change the date modified of a folder to the last changed file inside? [duplicate]

In my media center directory all modified times of my folders are somehow not the desired date. How can I change all modified times of the main folders to the modified time of the newest media-file ...
2
votes
2answers
1k views

Finding sparse files?

Is there a straightforward way to find all the sparse files on my system, or in a particular directory tree? If it's relevant, I'm using zsh on Ubuntu 12.04, although a more generic Unix-y answer for ...
2
votes
2answers
180 views

Symbolic link of for my user, doesn't work for root

I am experimenting with the following scheme in order to share common data among different distributions. In Fedora I have created a symbolic link /home pointing to: ...
4
votes
2answers
100 views

When I move a file to a different directory on the same partition, does the file's data actually move on disk?

I could see it going both ways. If the filesystem stores it's directory structure and list of files in each directory, and then points to the disk location of each of the files, it shouldn't require ...
3
votes
2answers
125 views

How to make directory modication date change when files from that dir change?

For example, if a file has been changed in that directory, then directory modification date should be updated. Basically any changes that happen in that directory should trigger a "touch" on the ...
28
votes
4answers
879 views

Append huge files to each other without copying them

There are 5 huge files ( file1, file2, .. file5) about 10G each and extremely low free space left on the disk and I need to concatenate all this files into one. There is no need to keep original ...
3
votes
2answers
166 views

Determining if a file system object is a procfs/sysfs/etc. “virtual file” which doesn't report its length correctly

Some kinds of pseudo-files, like many in the procfs and sysfs virtual file systems, have no file size (stat returns st_size == 0) and do not support SEEK_END in fseek. These file system objects, such ...
2
votes
3answers
111 views

determine user-modified files

I plan to reinstall my operating system since I messed up some stuff. Access to files and folders is painfully slow sometimes, even if they contain just a few files. But of course, I don't want to do ...
0
votes
1answer
96 views

What disk is a file / directory stored on? [duplicate]

From the command line (bash) I would like to know what disk a given file is stored in. E.G.: $ [what filesystem is this file in command] /tmp/example/file /dev/sda1
1
vote
2answers
150 views

How can find support large files?

I would like to find all the files of my system, which sizes are more than a couple gigabits. I thought I would use find -size, but the man page states: The size does not count indirect blocks ...
3
votes
2answers
72 views

Test if a file is on NFS?

Is there a simple test to determine if a file is on an NFS mount? (Or maybe more generally, what type of filesystem a file lives on?) I am imagining some ugly prefix matching against fstab...
0
votes
1answer
126 views

Unable to delete a directory even as root

I am unable to delete a directory even as root. The command rm -rf kdyiyv.pif returns nothing. Then I tried the command, touch kdyiyv.pif for which there was an error: touch: setting times of ...
2
votes
2answers
735 views

How does Linux know the Location of File Data on Disk

related to: What is a Superblock, Inode, Dentry and a File? None of the famous metadata structures hold onto to location data for the actual file. Dentry maps names to inodes, and inodes store ...
4
votes
2answers
1k views

How to upgrade shared library without crash?

Here it says that you can rewrite an executable file and the process will run just fine - it will be re-read when a process restarts. However, when I try to replace a binary file while the process is ...
3
votes
2answers
412 views

How can I backup a directory to NTFS while preserving Unix file attributes?

I want to make a backup of my home directory to an NTFS partition (an unfortunate limitation). However, when I last tried using just cp, the attributes (owner, etc) went away. How can I make a backup ...
1
vote
4answers
73 views

Is there a robust way to cache contents of usb on local hd?

I'd like to switch between working on a laptop with a debian vm and a desktop pc running debian while carrying all my work files in a usb. Is there a robust way to automatically start caching the ...
0
votes
1answer
244 views

how are directories implemented in UNIX filesystem?

This question is extension to How are directories implemented in Unix filesystems? I'm aiming to implement basic filesystem: After reading inode number and name we come to know Name of file and hence ...
1
vote
2answers
344 views

Cannot access any files Manjaro Linux

I cannot open any files on my Manjaro Linux laptop. I really can't remember why it happened but I restarted my computer and now I dont have read/write access to any folder or file even though I've ...
0
votes
1answer
1k views

Log4j File Location

I have a Webapp running on an Amazon EC2 Linux AMI. I've been trying to configure my Log4J file for logging but haven't been able to figure out where the logs are getting created. This is my log4j ...
0
votes
1answer
109 views

Debian VirtualBox Guest - Common Files to Remove for Space Saving?

I have created a VirtualBox guest using debian-6.0.7-amd64. I am using it as a clone template to create Java work nodes, so my needs are pretty much limited to the JVM, networking, SSH and the basics ...
5
votes
3answers
136 views

Control how linux deletes files

What exactly happens when an application deletes a file? Is there any way to control this behavior? Basically I want to shred instead of rm in all cases, but of course applications do not make calls ...