The following Linux commands are those I’ve come across that are used to manipulate files, and the notes I’ve made to help me remember what they do.

cp – copy

cp copies a file or directory from the source to the destination and leaves the original file intact

cp Documents/n* ~
#This will copy the all files beginning with lower case n in the Documents directory of the current working directory into the users HOME directory (~)

#directories cannot be copied this way and may cause errors. To view errors, use verbose mode eg:
cp -v Documents/n* ~
#this will display alerts as the copy operation runs.

#to copy directories use recursive options -r or -R
cp -R -v Documents/n* ~

file

file determines what content is contained by a file. This might be useful to prevent opening a file to read that cannot be handled by the terminal.

file Documents/noobot.txt
Displays:
Documents/noobot.txt: ASCII text

indicating that this is indeed a text file.

file /bin/cat
might display:
/bin/cat: ELF 32-bit LSB executable, ARM, EABI5 version 1 (SYSV), dynamically lin
ked, interpreter /lib/ld-linux-armhf.so.3, for GNU/Linux 3.2.0, BuildID[sha1]
=2239a192f2f277bd1a4892e39a41eba97266b91f, stripped

This is an Executable Link Format file which would not display well in the terminal if using a command like cat on it.

ls – list

ls is used to list files/directories
-a #displays all files including hidden
-A #as -a option but omits . and .. (current/parent directories)
-d #displays directory information only not files
-l #long listing
-r #reverses the order of a file sort
-R #lists recursively (ie displays contents of sub directories)
-S #sorts files by size
-t #sorts files by modified time

Long listing format:
drwxr-xr-x 1 mrnoobot  admin   2048 May 29 2020 noobdocs
d #denotes file type (see below - this is a directory)
rwxr-xr-x #file permissions - user/group/other - read/write/execute
1 #hard link count (only one directory links to this file)
mrnoobot #this field is the user owner
admin #this field is the group ownership
2048 #this field is the file size
May 29 2020 #last modified timestamp
noobdocs #file/directory name

File types:
d #directory
- #regular file
l #symbolic link
s #socket
p #pipe
b #block file
c #character file

mkdir – make directory

mkdir creates DIRECTORIES

mkdir noobdocs
#creates the directory noobdocs

mkdir noobdocs noobdocs1 noobdocs2
#creates multiple directories in the current working directory

mkdir -p noobdocs/noobdocs1/noobdocs2
#creates directories in a parent/child structure; eg noobdocs will be created in the current working directory; noobdocs1 will be created in noobdocs; noobdocs2 will be created in noobdocs1

mv – move

the mv command is similar to the cp command except it DOES NOT leave the source file intact; it physically moves it like a CUT/PASTE operation. The final argument will typically be a destination DIRECTORY. However, if the final argument is a FILENAME, then the file will be RENAMED.

mv noobfile changefile.txt
#renames the file noobfile to changefile.txt

mv noobfile Documents/noobdocs
#move a single file into directory noobdocs

mv noobfile noobfile1 noobfile2 Documents/noobdocs
#move multiple files into the directory noobdocs

rm – remove

rm can be used to remove FILES and recursively to remove DIRECTORIES AND THEIR CONTENTS

rm noobfile.txt

rm -i n*.txt
#adding i option prompts user for each file - without it the above command would delete all .txt files that start with lower case n.

rm -r noobdocs
#deletes the directory noobdocs AND EVERYTHING IN IT!

rmdir – remove directory

rmdir will delete EMPTY directories only. If trying to delete directories and contents, use rm recursively instead.

rmdir noobdocs
#deletes the EMPTY directory noobdocs. If it has any content an error will occur

rmdir -p noobdocs/noobdocs1/noobdocs2
#deletes the parent/child directory structure noobdocs/noobdocs1/noobdocs2 provided ALL directories are empty

touch

touch has a variety of uses including creating empty files and updating timestamps.

touch noobfile
#if noobfile does not exist, it will be created as an empty file
touch noobfile
#since it exists, the modified timestamp will be updated
-a #updates the accessed timestamp
-c #updates the file attribute modification timestamp (metadata)