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Questions tagged [ext4]

Ext 4 is a linux filesystem.

Ext4 is a filesystem mostly used under linux. Other versions are ext, ext2 and ext3.

See Wikipedia for details on ext and ext4.

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Extending ext4 File system's filename size limit to 1012 characters

I am pulling data from a server and one of the folder name is longer than 256 bytes, so my CentOS is throwing an error that the name is too long. I have searched all over the internet but couldn't find any way to create a folder/file name with size…
Sufiyan Ghori
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Why does Python give "OSError: [Errno 36] File name too long" for filename shorter than filesystem's limit?

The following code yields an unexpected exception: open("52bbe674cdc81d4140099b84fa69eea4249bcceee75bcbe4838d911ab076547cfdad3c1c5197752a98e5525fe76613dbe52dcdb1a9a397669babce0f101d010142cffa000000.csv", "w") OSError: [Errno 36] File name too long:…
Josh Hansen
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Is lseek() O(1) complexity?

I know that my question has an answer here: QFile seek performance. But I am not completely satisfied with the answer. Even after looking at the following implementation of generic_file_llseek() for ext4, I can't seem to understand how can the…
Nehal J Wani
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Setting/changing the ctime or "Change time" attribute on a file

I wish to change the timestamp metadata on files in Java using the java.nio.Files class. I would like to change all 3 Linux/ext4 timestamps (last modified, access, and changed). I am able to change the first two timestamp fields as…
Eitan
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timestamp accuracy on EXT4 (sub millsecond)

I was writing some code in Vala where I would first get the system time, then create a file, then retrieve the time stamp of that file. The timestamp would always be earlier that the system time, somewhere between 500 and 1500 micro seconds which…
Wayne
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Accessing ext3 / ext4 journals

ext3 and ext4 file systems have journaling. Is there any chance there's some API to get details or events about files? Some kind of API that will allow a user space program to access journal entries for files. Or even journal events, like "file x…
Gaurav Mahajan
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ext4 Specifications?

Where can I find the ext4 file system specifications? (Unofficial drafts are fine, so long as they're reasonably up-to-date; if unavailable, ext3 would be fine too.)
user541686
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Modifying data written to disk by Ext4 filesystem

I'm working on the academic project, part of which is applying transparent encryption (AES-CTR) to the selected Ext4 files stored on the disk (I can already mark them as encrypted using new ioctl etc.,). In order to do so, I need to find the best…
Tomek Falkiewicz
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Recover files deleted with rsync -avz --delete

Is it possible to recover files deleted with rsync -avz --delete? If it is, what are some suggested tools to do so?
Ben J
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Performance of postgresql with large numbers of tables (EG: 1 million tables)?

What is the largest number of tables that can be within a single pgsql database while still retaining good performance, given that pgsql stores 1 file per table on the filesystem and searches the pg_catalog for every query to do query planning? EG:…
archmeta
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python - read file info, permissions from raw ext4 image

I am trying to unpack android 11 image / get info from the raw .img for selinux info, symlinks etc. I am using this wonderful tool: https://github.com/cubinator/ext4/blob/master/ext4.py35.py and my code looks like this: #!/usr/bin/env…
Margarita Weiß
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EC2 Instance, mount volume DOS/MBR boot sector

I'm trying to mount the main /dev/sda1 volumen from an EC2 instance, to a new one, but I have these issues: $ sudo mount -t ext4 /dev/xvdg /mnt/xvdg/ mount: wrong fs type, bad option, bad superblock on /dev/xvdg, missing codepage or helper…
eft0
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How does the length of a filename affect remaining storage space on a disk?

How does the length of a filename affect remaining storage space on a disk? I realize this is filesystem dependent. In particular I am thinking about the EXT series of file systems. I don't fully understand how inodes affect disk space and how the…
SO Stinks
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Patching and compiling Ext4 as a kernel module

I'm currently patching Ext4 for academic purposes (only linux/fs/ext4/*, like file.c, ioctl.c, ext4.h) . I'm working on the QEMU virtual machine, and to speed up the whole process I've selected Ext4 to compile as a kernel module. The problem occurs…
Tomek Falkiewicz
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Preventing backslash in path building on .NET for cross platform deploy

I have a legacy .NET application that I have ported to .NET 6.0 and am executing cross platform (Windows & Linux). Much of the legacy code was developed with hard coded path creation, using backslash in strings, like new…
Kevin Kostrzewa
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