Windows & POSIX CLI Reference

A comprehensive command-line reference comparing equivalent utilities between Windows and POSIX-compliant systems (Linux, macOS, FreeBSD). Organised into logical sections covering the most commonly used system administration and file management tasks for desktop and server environments.

File Operations

Task	POSIX Systems	Windows	Notes
Display file contents	cat filename	type filename	Both systems support more
Copy file	cp source dest	copy source dest	Both support recursive copying with options
Move/rename file	mv oldname newname	move oldname newname	Windows also has ren, POSIX has rename
Delete file	rm filename	del filename	Windows also supports erase
Delete file forcefully	rm -f filename	del /f filename	Force deletion of read-only files
Delete recursively	rm -rf directory	rmdir /s directory	Windows also supports rd /s
Create empty file	touch filename	echo. > filename	Windows: type nul > filename also works
Find files	find /path -name "*.txt"	dir /s *.txt	Windows: forfiles for advanced searches
Compare files	diff file1 file2	fc file1 file2	Windows: comp for binary comparison
File permissions	chmod 755 filename	icacls filename /grant user:F	Different permission models entirely
File ownership	chown user:group filename	takeown /f filename	Windows: icacls for detailed permissions

Directory Operations

Task	POSIX Systems	Windows	Notes
List directory contents	ls	dir	POSIX: ls -la for detailed view
List with details	ls -l	dir /q	Show ownership and permissions
List hidden files	ls -a	dir /a	Include hidden and system files
Create directory	mkdir dirname	mkdir dirname	Both support -p for parent directories
Remove empty directory	rmdir dirname	rmdir dirname	Directory must be empty
Current directory	pwd	cd	Windows: echo %cd% also works
Change directory	cd /path/to/dir	cd \path\to\dir	Use forward/back slashes respectively
Directory size	du -sh dirname	dir /s dirname	Windows: shows total size at end
Directory tree	tree	tree	Both systems have tree command

Text Processing

Task	POSIX Systems	Windows	Notes
Search text in files	grep "pattern" filename	findstr "pattern" filename	Windows: /i for case-insensitive
Search recursively	grep -r "pattern" /path	findstr /s "pattern" *	Search in subdirectories
Count lines	wc -l filename	find /c /v "" filename	Windows counts non-empty lines
Head of file	head -n 10 filename	more +10 filename	Windows: limited built-in options
Tail of file	tail -n 10 filename	powershell Get-Content filename -Tail 10	Windows: PowerShell required for tail
Sort file contents	sort filename	sort filename	Both systems support sorting
Remove duplicates	sort filename \| uniq	sort filename \| uniq	Windows has limited uniq functionality
Replace text	sed 's/old/new/g' filename	powershell (Get-Content file) -replace 'old','new'	Windows: PowerShell for advanced replacement

Network Operations

Task	POSIX Systems	Windows	Notes
Test connectivity	ping hostname	ping hostname	Both support same basic options
Trace route	traceroute hostname	tracert hostname	Different command names
Network configuration	ip addr show	ipconfig	POSIX: ifconfig on older systems
DNS lookup	nslookup hostname	nslookup hostname	Both systems identical
Network connections	netstat -an	netstat -an	Both systems identical
Active connections	ss -tuln	netstat -an \| findstr LISTEN	POSIX ss is modern replacement
Download file	wget url	powershell Invoke-WebRequest url	Windows: curl available in newer versions
Show routing table	route -n	route print	Different syntax
ARP table	arp -a	arp -a	Both systems identical
Flush DNS cache	sudo systemctl restart systemd-resolved	ipconfig /flushdns	POSIX varies by distribution

System Information

Task	POSIX Systems	Windows	Notes
System information	uname -a	systeminfo	Windows provides more detailed output
OS version	cat /etc/os-release	ver	POSIX location varies by distribution
Hostname	hostname	hostname	Both systems identical
Uptime	uptime	systeminfo \| findstr "System Boot Time"	Windows: more verbose
Memory usage	free -h	wmic OS get TotalVisibleMemorySize,FreePhysicalMemory /value	Windows: WMI query
Disk usage	df -h	wmic logicaldisk get size,freespace,caption	Windows: WMI query
CPU information	lscpu	wmic cpu get name,numberofcores,numberoflogicalprocessors /value	Windows: WMI query
Hardware info	lshw	wmic computersystem get model,manufacturer /value	POSIX: may need installation
Environment variables	env	set	List all environment variables
Specific env variable	echo $PATH	echo %PATH%	Different syntax for variables

Process Management

Task	POSIX Systems	Windows	Notes
List processes	ps aux	tasklist	POSIX: many options available
Kill process by PID	kill 1234	taskkill /pid 1234	Windows: /f to force
Kill process by name	killall processname	taskkill /im processname.exe	Windows: include .exe extension
Process tree	pstree	tasklist /v	Windows: limited tree view
Top processes	top	tasklist /fi "memusage gt 100000"	Windows: filter by memory usage
Background process	command &	start /b command	Run process in background
Process priority	nice -n 10 command	start /low command	Set process priority
Process monitoring	htop	tasklist /fi "status eq running"	POSIX htop may need installation

User Management

Task	POSIX Systems	Windows	Notes
Current user	whoami	whoami	Both systems identical
List users	cat /etc/passwd	net user	Different approaches
Add user	sudo useradd username	net user username password /add	Admin privileges required
Delete user	sudo userdel username	net user username /delete	Admin privileges required
Change password	passwd	net user username *	Interactive password change
User groups	groups username	net user username	Windows shows group membership
Switch user	su - username	runas /user:username cmd	Different syntax
Sudo equivalent	sudo command	runas /user:administrator cmd	Windows: Run as administrator

File Permissions & Security

Task	POSIX Systems	Windows	Notes
View permissions	ls -l filename	icacls filename	Windows shows ACLs
Change permissions	chmod 755 filename	icacls filename /grant user:RX	Different permission models
Change ownership	chown user:group filename	takeown /f filename	Windows: separate ownership command
Set file attributes	chattr +i filename	attrib +r filename	Different attribute systems
View file attributes	lsattr filename	attrib filename	Different commands

Archive Operations

Task	POSIX Systems	Windows	Notes
Create tar archive	tar -czf archive.tar.gz files	powershell Compress-Archive files archive.zip	Different formats
Extract tar archive	tar -xzf archive.tar.gz	powershell Expand-Archive archive.zip	PowerShell for zip
List archive contents	tar -tzf archive.tar.gz	powershell Get-ChildItem archive.zip	PowerShell required
Create zip archive	zip -r archive.zip files	powershell Compress-Archive files archive.zip	zip may need installation on POSIX

Environment & Variables

Task	POSIX Systems	Windows	Notes
Set variable	export VAR=value	set VAR=value	POSIX: session-wide, Windows: temporary
Unset variable	unset VAR	set VAR=	Windows: set to empty string
Persistent variable	echo 'export VAR=value' >> ~/.bashrc	setx VAR value	Different persistence methods
Show PATH	echo $PATH	echo %PATH%	Different variable syntax
Add to PATH	export PATH=$PATH:/new/path	set PATH=%PATH%;C:\new\path	Different path separators (: vs ;)

Common Environment Variables

Purpose	POSIX Systems	Windows (CMD)	Windows (PowerShell)	Notes
Current user	$USER or $LOGNAME	%USERNAME%	$env:USERNAME	Username of logged-in user
User home directory	$HOME	%USERPROFILE%	$env:USERPROFILE	User’s home folder path
Current directory	$PWD	%CD%	$PWD	Present working directory
System PATH	$PATH	%PATH%	$env:PATH	Executable search paths
Hostname	$HOSTNAME	%COMPUTERNAME%	$env:COMPUTERNAME	Computer/machine name
Operating system	$OSTYPE	%OS%	$env:OS	Operating system identifier
Temp directory	$TMPDIR or /tmp	%TEMP% or %TMP%	$env:TEMP	Temporary files location
Shell/Command proc	$SHELL	%COMSPEC%	$PSVersionTable	Default shell/command processor
System root	/	%SYSTEMROOT%	$env:SYSTEMROOT	System installation directory
Program files	/usr or /opt	%PROGRAMFILES%	$env:PROGRAMFILES	Default program installation directory
System architecture	$HOSTTYPE or uname -m	%PROCESSOR_ARCH%	$env:PROCESSOR_ARCH	CPU architecture (x86, x64, ARM)
Number of CPUs	$NPROC or nproc	%NUMBER_OF_PROC%	$env:NUMBER_OF_PROC	Available processor cores
User profile path	$HOME	%USERPROFILE%	$HOME	User’s profile directory
Application data	$HOME/.config	%APPDATA%	$env:APPDATA	User application data directory
Local app data	$HOME/.local/share	%LOCALAPPDATA%	$env:LOCALAPPDATA	Local application data directory
Desktop path	$HOME/Desktop	%USERPROFILE%\Desktop	$HOME\Desktop	User’s desktop folder
Documents path	$HOME/Documents	%USERPROFILE%\Docs	$HOME\Documents	User’s documents folder
System drive	N/A (use /)	%SYSTEMDRIVE%	$env:SYSTEMDRIVE	Drive containing Windows (usually C:)
Random number	$RANDOM	%RANDOM%	Get-Random	Generate random number
Date/Time	$DATE or date	%DATE% / %TIME%	Get-Date	Current date and time
Error level	$?	%ERRORLEVEL%	$LASTEXITCODE	Exit code of last command
Process ID	$$	N/A	$PID	Current process identifier
Terminal type	$TERM	N/A	$Host.Name	Terminal/console type
Display (GUI)	$DISPLAY	N/A	N/A	X11 display for GUI applications
Language/Locale	$LANG or $LC_ALL	N/A	$PSCulture	System language and locale settings

Accessing Environment Variables

Task	POSIX Systems	Windows (CMD)	Windows (PowerShell)	Notes
Display single var	echo $VAR	echo %VAR%	echo $env:VAR	Show specific variable
Display all vars	env or printenv	set	Get-ChildItem env:	List all environment vars
Check if var exists	[ -n "$VAR" ]	if defined VAR	Test-Path env:VAR	Test variable existence
Set temporary var	VAR=value	set VAR=value	$env:VAR = "value"	Session-only variable
Set permanent var	export VAR=value	setx VAR value	[Environment]::SetVariable	Persistent across sessions
Unset variable	unset VAR	set VAR=	Remove-Item env:VAR	Remove environment variable

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Logic and Conditional Operators

Command Chaining and Logic

Operation	Bash/POSIX Shell	Windows CMD	PowerShell	Notes
AND (success chain)	command1 && command2	command1 && command2	command1; command2	Run second if first succeeds
OR (failure chain)	command1 \|\| command2	command1 \|\| command2	command1; if (!$?) { command2 }	Run second if first fails
Sequential	command1; command2	command1 & command2	command1; command2	Run both regardless of result
Pipe output	command1 \| command2	command1 \| command2	command1 \| command2	Pass output to next command

Comparison Operators

Comparison	Bash	Windows CMD	PowerShell	Notes
Equal	[ "$a" -eq "$b" ]	if %a%==%b%	$a -eq $b	String/numeric equality
Not equal	[ "$a" -ne "$b" ]	if not %a%==%b%	$a -ne $b	String/numeric inequality
Greater than	[ "$a" -gt "$b" ]	if %a% gtr %b%	$a -gt $b	Numeric comparison
Less than	[ "$a" -lt "$b" ]	if %a% lss %b%	$a -lt $b	Numeric comparison
Greater or equal	[ "$a" -ge "$b" ]	if %a% geq %b%	$a -ge $b	Numeric comparison
Less or equal	[ "$a" -le "$b" ]	if %a% leq %b%	$a -le $b	Numeric comparison
String equal	[ "$a" = "$b" ]	if "%a%"=="%b%"	$a -eq $b	Exact string match
String not equal	[ "$a" != "$b" ]	if not "%a%"=="%b%"	$a -ne $b	String inequality

File and Directory Tests

Test	Bash	Windows CMD	PowerShell	Notes
File exists	[ -f "$file" ]	if exist "%file%"	Test-Path $file	Check if file exists
Directory exists	[ -d "$dir" ]	if exist "%dir%\"	Test-Path $dir -PathType Container	Check if directory exists
File readable	[ -r "$file" ]	N/A	(Get-Acl $file).Access	Check read permissions
File writable	[ -w "$file" ]	N/A	(Get-Acl $file).Access	Check write permissions
File executable	[ -x "$file" ]	N/A	(Get-Command $file -ErrorAction SilentlyContinue)	Check execute permissions
File empty	[ ! -s "$file" ]	if %~z1==0	(Get-Item $file).Length -eq 0	Check if file is empty

Exit Codes and Error Handling

Operation	Bash	Windows CMD	PowerShell	Notes
Last exit code	echo $?	echo %errorlevel%	echo $LASTEXITCODE	Show previous command result
Exit with code	exit 1	exit /b 1	exit 1	Exit script with specific code
Success (exit 0)	exit 0	exit /b 0	exit 0	Successful completion
Suppress errors	command 2>/dev/null	command 2>nul	command -ErrorAction SilentlyContinue	Hide error output

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Tips for Cross-Platform Usage

1. Path Separators: POSIX uses / while Windows uses \ (though Windows accepts / in many contexts)
2. Case Sensitivity: POSIX is case-sensitive, Windows is not
3. Line Endings: POSIX uses LF (\n), Windows uses CRLF (\r\n)
4. Wildcards: Both support * and ?, but behavior may vary
5. Permissions: POSIX uses octal permissions (755), Windows uses Access Control Lists (ACLs)
6. Environment Variables: POSIX uses $VAR, Windows uses %VAR%
7. Command Chaining: Both support && (AND) and || (OR), POSIX also supports ;
8. Redirection: Both support > (redirect), >> (append), and | (pipe)

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POSIX Only

Package Management Comparison

Task	Debian/Ubuntu (APT)	Red Hat/Fedora (DNF/YUM)	FreeBSD (pkg)	Notes
Update package list	sudo apt update	sudo dnf check-update	sudo pkg update	Refresh repository metadata
Upgrade packages	sudo apt upgrade	sudo dnf upgrade	sudo pkg upgrade	Install available updates
Install package	sudo apt install package	sudo dnf install package	sudo pkg install package	Install new software
Remove package	sudo apt remove package	sudo dnf remove package	sudo pkg delete package	Remove software
Search packages	apt search keyword	dnf search keyword	pkg search keyword	Find available packages
Show package info	apt show package	dnf info package	pkg info package	Display package details
List installed	apt list --installed	dnf list installed	pkg info	Show installed packages
Clean cache	sudo apt clean	sudo dnf clean all	sudo pkg clean	Clear package cache
Autoremove unused	sudo apt autoremove	sudo dnf autoremove	sudo pkg autoremove	Remove orphaned packages

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Windows Only

PowerShell

Task	Command	Notes
List processes	Get-Process	PowerShell alternative to tasklist
Stop process	Stop-Process -Name processname	PowerShell process management
Get system info	Get-ComputerInfo	Comprehensive system information
Network adapters	Get-NetAdapter	Modern network configuration
Event logs	Get-EventLog -LogName System	View system events
Services	Get-Service	List Windows services
Install software	winget install package	Package manager (Windows 10+)

Windows Subsystem for Linux (WSL)

Task	Command	Notes
List distributions	wsl --list	Show installed Linux distributions
Set default distro	wsl --set-default Ubuntu	Change default Linux environment
Run specific distro	wsl -d Ubuntu	Launch specific distribution
Shutdown WSL	wsl --shutdown	Stop all WSL instances

Terminology Acronyms

Acronym	Full Form	Description
ACL	Access Control List	Windows file permission system
APT	Advanced Package Tool	Debian/Ubuntu package management system
ARP	Address Resolution Protocol	Network protocol for IP to MAC address mapping
BSD	Berkeley Software Distribution	Unix-like operating system family
DNF	Dandified YUM	Modern package manager for Red Hat-based distributions
DNS	Domain Name System	Internet naming system
PID	Process Identifier	Unique number assigned to running processes
POSIX	Portable Operating System Interface	IEEE standard for Unix-like operating system compatibility
SSH	Secure Shell	Encrypted network protocol for remote access
TTY	Teletypewriter	Terminal interface
WMI	Windows Management Instrumentation	Windows system management interface
WSL	Windows Subsystem for Linux	Linux compatibility layer for Windows
YUM	Yellowdog Updater Modified	Legacy package manager for Red Hat-based distributions

Command Acronyms

Command	Full Form	Description
cat	Concatenate	Display and concatenate file contents
cd	Change Directory	Navigate between directories
cp	Copy	Copy files and directories
df	Disk Free	Display filesystem disk space usage
du	Disk Usage	Display directory space usage
grep	Global Regular Expression Print	Search text using patterns
ls	List	List directory contents
mv	Move	Move/rename files and directories
ps	Process Status	Display running processes
pwd	Print Working Directory	Display current directory path
rm	Remove	Delete files and directories
sed	Stream Editor	Stream-oriented text editor for filtering/transform
su	Switch User (or Substitute User)	Change user identity
tar	Tape Archive	Archive files (originally for tape storage)
wc	Word Count	Count lines, words, and characters