07272022.md

1. Scan Windows system and catch log:

sfc /scannow
findstr /c:"[SR]" %windir%\Logs\CBS\CBS.log >C:\Users\<username>\Desktop\sfcdetails.txt

2. System/Builtin variables in cmd: (batch script)

• Builtin variables:

VARIABLE	WINDOWS 10
%ALLUSERSPROFILE%	C:\ProgramData
%APPDATA%	C:\Users\{username}\AppData\Roaming
%COMMONPROGRAMFILES%	C:\Program Files\Common Files
%COMMONPROGRAMFILES(x86)%	C:\Program Files (x86)\Common Files
%CommonProgramW6432%	C:\Program Files\Common Files
%COMSPEC%	C:\Windows\System32\cmd.exe
%HOMEDRIVE%	C:\
%HOMEPATH%	C:\Users\{username}
%LOCALAPPDATA%	C:\Users\{username}\AppData\Local
%LOGONSERVER%	\\{domain_logon_server}
%PATH%	C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem
%PathExt%	.com;.exe;.bat;.cmd;.vbs;.vbe;.js;.jse;.wsf;.wsh;.msc
%PROGRAMDATA%	C:\ProgramData
%PROGRAMFILES%	C:\Program Files
%ProgramW6432%	C:\Program Files
%PROGRAMFILES(X86)%	C:\Program Files (x86)
%PROMPT%	$P$G
%SystemDrive%	C:
%SystemRoot%	C:\Windows
%TEMP%	C:\Users\{username}\AppData\Local\Temp
%TMP%	C:\Users\{username}\AppData\Local\Temp
%USERDOMAIN%	Userdomain associated with current user.
%USERDOMAIN_ROAMINGPROFILE%	Userdomain associated with roaming profile.
%USERNAME%	{username}
%USERPROFILE%	C:\Users\{username}
%WINDIR%	C:\Windows
%PUBLIC%	C:\Users\Public
%PSModulePath%	%SystemRoot%\system32\WindowsPowerShell\v1.0\Modules\
%OneDrive%	C:\Users\{username}\OneDrive
%DriverData%	C:\Windows\System32\Drivers\DriverData
%CD%	Outputs current directory path. (Command Prompt.)
%CMDCMDLINE%	Outputs command line used to launch current Command Prompt session. (Command Prompt.)
%CMDEXTVERSION%	Outputs the number of current command processor extensions. (Command Prompt.)
%COMPUTERNAME%	Outputs the system name.
%DATE%	Outputs current date. (Command Prompt.)
%TIME%	Outputs time. (Command Prompt.)
%ERRORLEVEL%	Outputs the number of defining exit status of previous command. (Command Prompt.)
%PROCESSOR_IDENTIFIER%	Outputs processor identifier.
%PROCESSOR_LEVEL%	Outputs processor level.
%PROCESSOR_REVISION%	Outputs processor revision.
%NUMBER_OF_PROCESSORS%	Outputs the number of physical and virtual cores.
%RANDOM%	Outputs random number from 0 through 32767.
%OS%	Windows_NT

$ echo %systemroot%
C:\WINDOWS

$ echo %userprofile%
C:\Users\<username>

$ echo %windir%
C:\WINDOWS

$ echo %appdata%
C:\Users\<username>\AppData\Roaming

• List all environments variable:

  • List all environment variables (cmd.exe):

    set
    setx [variable_name] "[variable_value]"

  • Show value of a specific variable (powershell.exe / pwsh.exe):

    echo $Env:[variable_name]

  • Manage using Registry Editor:

    reg query HKEY_CURRENT_USER\Environment
    reg query HKEY_CURRENT_USER\Environment /v [variable_name]
    reg delete HKEY_CURRENT_USER\Environment /v [variable_name] /f
    
    reg query "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Environment"
    reg query "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Environment" /v [variable_name]
    reg delete "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Environment" /v [variable_name] /f
    
    reg add "HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings" /v "ProxyServer" /t REG_SZ /d "http://procycorp.bac:80" /f
    reg add "HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings" /v "ProxyEnable" /t REG_DWORD /d "0" /f

  • bitsadmin: BITS administration utility:

    @REM Admin privileges required to become all executable commands:
    bitsadmin /util /setieproxy localsystem MANUAL_PROXY procycorp.bac:80 "localhost"
    bitsadmin /util /getieproxy localsystem

3. Multi-line comments in Bash script: cyberciti.biz

• Using HERE Document:

<<COMMENT
  Your comment1
  Your comment2
  Your comment3
COMMENT

• Using comment block: put EOF here to avoid command execution and phrasing

: <<'EOF'
CODE block starts
CODE block ends
EOF

• Using multi-line shell script comments:

  • : (colon) := [arguments] No effect; the command does nothing beyond expanding arguments and performing any specified redirections. A zero exit code is returned.

: '
Your comment1
Your comment2
Your comment3
'