File - jasper-zanjani/dotfiles GitHub Wiki

• chattr
• chgrp
• chmod
• chown
• cksum
• cp
• curl
• dd
• dirname
• dos2unix
• exif
• fallocate
• file
• find
• getfacl
• install
• link
• ln
• locate
• ls
• lsattr
• lsof
• md5sum
• mkdir
• mktemp
• mv
• rename
• rm
• rmdir
• rsync
• scp
• setfacl
• setuid
• stat
• touch
• tree
• umask
• unlink
• updatedb
• whereis
• which

View image metadata. Unlike alternatives like file and ImageMagick's identify, exif produces columnar output [^ref][31]

exif image.png 

Create a file size of 1 gigabyte

fallocate -l 1G $FILENAME  # gibibyte
fallocate -l 1GB $FILENAME # gigabyte

View image metadata ^{ostechnix.com}

file image.png # => file type, dimensions, color depth

Search for files in a directory hierarchy Find all files in {$PATH} that are owned by {user}

find $PATH -user username

Find recently modified files/folders There are 3 timestamps associated with files in Linux ^2daygeek.com

• atime "access time": last time file was accessed by a command or application
• mtime "modify time": last time file's contents were modified
• ctime "change time": last time file's attribute was modified

Numerical arguments can be specified in 3 ways:

• +n greater than {n} days ago
• -n less than {n} days ago
• n exactly {n} days ago

find $PATH -type f -mtime +120 -ls # Find only files that were modified more than 120 days ago
find $PATH -type f -mtime -15 -ls # Modified less than 15 days ago
find $PATH -type f -mtime 10 -ls # Modified exactly 10 days ago

# Find files modified over the past day
find $PATH -type f -newermt "1 day ago" -ls
find $PATH -type f -newermt "-24 hours" -ls
find $PATH -type f -newermt "yesterday" -ls

find $PATH -type f -ctime -1 -ls # Find files created today

Copy files while maintaining various metadata, including timestamp, owner, etc. [9]

Copy a file while preserving timestamp. The copy will have the install default of 755, but the original's mtime is maintained:

install --preserve-timestamp example/foo .

Copy a file, setting permissions, owner, and group

install --preserve-timestamp --owner=jdoe --group=sudoers --mode=753

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Display open files, open network ports, and network connections [23]

Show open network connections

sudo lsof -Pni

Quickly create multiple directories using brace expansion

mkdir -p ~/my-app/{bin,lib,log}

Create new directory {dirname} along with all of the parents in its pathname, if they do not exist

mkdir -p dirname
mkdir --parents dirname

rename uses regular expressions ^{[Network World][https://www.networkworld.com/article/3433865/how-to-rename-a-group-of-files-on-linux.html#tk.rss_linux]}

Rename multiple files

# Renaming file.old to file.new
rename 's/old/new/' this.old

# Use globbing to rename all matching files
rename 's/old/new/' *.old
rename 's/report/review/' *

# Change all uppercase letters to lowercase
rename 'y/A-Z/a-z/' *

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Copy $FILE locally ^2daygeek.com

rsync -zvr $FILE $PATH

Copy $FILE to $PATH on remote $HOST

rsync $FILE $HOST:$PATH

Copy $FILE from $HOST to local $PATH

rsync $HOST:$FILE $PATH

Copy $DIR recursively ^2daygeek.com

rsync -zvr $DIR $PATH
rsync -avz $DIR $PATH

Copy to remote systems over SSH ^2daygeek.com

rsync -zvre ssh $DIR $HOST:$REMOTEPATH
rsync -avze ssh $DIR $HOST:$REMOTEPATH

Synchronize only specific file type ^2daygeek.com

rsync -zvre ssh --include '*.php' --exclude '*' $PATH

Set file access control list

Grant user {lisa} right to read {file}

setfacl -m u:lisa:r file

Remove named group {staff} from {file}'s ACL

setfacl -x g:staff file

Modify file access control list for {file} to revoke write access from all groups and all named users

setfacl -m m::rx file

Grant read access to other users

setfacl -m o::rwx file4.txt

Add user {zach} to list of users of file4.txt

setfacl -m u:zach:rw file4.txt

Write random data to an unmounted disk for {n} passes

shred --iterations=n

^{Network World}

Display contents of directories in a tree-like format ^{[tecmint.com]}(https://www.tecmint.com/linux-tree-command-examples/ "tecmint.com: "Linux tree command usage examples for beginners"")