A fast alternative to color efficiently with cmd batch since Windows XP by using PowerShell as a subprocess linked to the console output through a named pipe. It can be done with FindStr too, but PowerShell offers more options and seems quicker.
The main interest in keeping PowerShell as a subprocess, using a pipe to communicate, is that the display is far more faster than launching PowerShell or FindStr for each line to display.
Other good points :
- No need for temporary files
- Echoing though a pipe permits the display of the full ASCII table without bothering escapes.
- Works fine with fd redirection. To color only stderr as example, or to redirect to a file / other process.
Here is a sample code for doing that :
::
:: Launch a PowerShell child process in the background linked to the console and
:: earing through named pipe PowerShellCon_%PID%
::
:: Parameters :
:: [ PID ] : Console Process ID used as an identifier for the named pipe, launcher PID by default.
:: [ timeout ] : Subprocess max life in seconds, 300 by default. If -1, the subprocess
:: will not terminate while the process %PID% is still alive.
:: Return :
:: 0 if the child PowerShell has been successfully launched and the named pipe is available.
:: 1 if it fails.
:: 2 if we can't get a PID.
:: 3 if PowerShell is not present or doesn't work.
::
:LaunchPowerShellSubProcess
SET LOCALV_PID=
SET LOCALV_TIMEOUT=300
IF NOT "%~1" == "" SET LOCALV_PID=%~1
IF NOT "%~2" == "" SET LOCALV_TIMEOUT=%~2
powershell -command "$_" 2>&1 >NUL
IF NOT "!ERRORLEVEL!" == "0" EXIT /B 3
IF "!LOCALV_PID!" == "" (
FOR /F %%P IN ('powershell -command "$parentId=(Get-WmiObject Win32_Process -Filter ProcessId=$PID).ParentProcessId; write-host (Get-WmiObject Win32_Process -Filter ProcessId=$parentId).ParentProcessId;"') DO (
SET LOCALV_PID=%%P
)
)
IF "!LOCALV_PID!" == "" EXIT /B 2
START /B powershell -command "$cmdPID=$PID; Start-Job -ArgumentList $cmdPID -ScriptBlock { $ProcessActive = $true; $timeout=!LOCALV_TIMEOUT!; while((!LOCALV_TIMEOUT! -eq -1 -or $timeout -gt 0) -and $ProcessActive) { Start-Sleep -s 1; $timeout-=1; $ProcessActive = Get-Process -id !LOCALV_PID! -ErrorAction SilentlyContinue; } if ($timeout -eq 0 -or ^! $ProcessActive) { Stop-Process -Id $args; } } | Out-Null ; $npipeServer = new-object System.IO.Pipes.NamedPipeServerStream('PowerShellCon_!LOCALV_PID!', [System.IO.Pipes.PipeDirection]::In); Try { $npipeServer.WaitForConnection(); $pipeReader = new-object System.IO.StreamReader($npipeServer); while(($msg = $pipeReader.ReadLine()) -notmatch 'QUIT') { $disp='write-host '+$msg+';'; invoke-expression($disp); $npipeServer.Disconnect(); $npipeServer.WaitForConnection(); }; } Finally { $npipeServer.Dispose(); }" 2>NUL
SET /A LOCALV_TRY=20 >NUL
:LaunchPowerShellSubProcess_WaitForPipe
powershell -nop -c "& {sleep -m 50}"
SET /A LOCALV_TRY=!LOCALV_TRY! - 1 >NUL
IF NOT "!LOCALV_TRY!" == "0" cmd /C "ECHO -NoNewLine|MORE 1>\\.\pipe\PowerShellCon_!LOCALV_PID!" 2>NUL || GOTO:LaunchPowerShellSubProcess_WaitForPipe
IF "!LOCALV_TRY!" == "0" EXIT /B 1
EXIT /B 0
This "code" is written with delayed expansion ON but can be rewrite to work without it. There is many security points to consider, do not use it directly in the wild.
How to use it :
@ECHO OFF
SETLOCAL ENABLEEXTENSIONS
IF ERRORLEVEL 1 (
ECHO Extension inapplicable
EXIT /B 1
)
::
SETLOCAL ENABLEDELAYEDEXPANSION
IF ERRORLEVEL 1 (
ECHO Expansion inapplicable
EXIT /B 1
)
CALL:LaunchPowerShellSubProcess
IF NOT ERRORLEVEL 0 EXIT /B 1
CALL:Color Cyan "I write this in Cyan"
CALL:Blue "I write this in Blue"
CALL:Green "And this in green"
CALL:Red -nonewline "And mix Red"
CALL:Yellow "with Yellow"
CALL:Green "And not need to trouble with ()<>&|;,%""^ and so on..."
EXIT /B 0
:Color
ECHO -foregroundcolor %*>\\.\pipe\PowerShellCon_!LOCALV_PID!
ECHO[|SET /P=>NUL
GOTO:EOF
:Blue
ECHO -foregroundcolor Blue %*>\\.\pipe\PowerShellCon_!LOCALV_PID!
ECHO[|SET /P=>NUL
GOTO:EOF
:Green
ECHO -foregroundcolor Green %*>\\.\pipe\PowerShellCon_!LOCALV_PID!
ECHO[|SET /P=>NUL
GOTO:EOF
:Red
ECHO -foregroundcolor Red %*>\\.\pipe\PowerShellCon_!LOCALV_PID!
ECHO[|SET /P=>NUL
GOTO:EOF
:Yellow
ECHO -foregroundcolor Yellow %*>\\.\pipe\PowerShellCon_!LOCALV_PID!
ECHO[|SET /P=>NUL
GOTO:EOF
::
:: Launch a PowerShell child process in the background linked to the console and
:: earing through named pipe PowerShellCon_%PID%
::
:: Parameters :
:: [ PID ] : Console Process ID used as an identifier for the named pipe, launcher PID by default.
:: [ timeout ] : Subprocess max life in seconds, 300 by default. If -1, the subprocess
:: will not terminate while the process %PID% is still alive.
:: Return :
:: 0 if the child PowerShell has been successfully launched and the named pipe is available.
:: 1 if it fails.
:: 2 if we can't get a PID.
:: 3 if PowerShell is not present or doesn't work.
::
:LaunchPowerShellSubProcess
SET LOCALV_PID=
SET LOCALV_TIMEOUT=300
IF NOT "%~1" == "" SET LOCALV_PID=%~1
IF NOT "%~2" == "" SET LOCALV_TIMEOUT=%~2
powershell -command "$_" 2>&1 >NUL
IF NOT "!ERRORLEVEL!" == "0" EXIT /B 3
IF "!LOCALV_PID!" == "" (
FOR /F %%P IN ('powershell -command "$parentId=(Get-WmiObject Win32_Process -Filter ProcessId=$PID).ParentProcessId; write-host (Get-WmiObject Win32_Process -Filter ProcessId=$parentId).ParentProcessId;"') DO (
SET LOCALV_PID=%%P
)
)
IF "!LOCALV_PID!" == "" EXIT /B 2
START /B powershell -command "$cmdPID=$PID; Start-Job -ArgumentList $cmdPID -ScriptBlock { $ProcessActive = $true; $timeout=!LOCALV_TIMEOUT!; while((!LOCALV_TIMEOUT! -eq -1 -or $timeout -gt 0) -and $ProcessActive) { Start-Sleep -s 1; $timeout-=1; $ProcessActive = Get-Process -id !LOCALV_PID! -ErrorAction SilentlyContinue; } if ($timeout -eq 0 -or ^! $ProcessActive) { Stop-Process -Id $args; } } | Out-Null ; $npipeServer = new-object System.IO.Pipes.NamedPipeServerStream('PowerShellCon_!LOCALV_PID!', [System.IO.Pipes.PipeDirection]::In); Try { $npipeServer.WaitForConnection(); $pipeReader = new-object System.IO.StreamReader($npipeServer); while(($msg = $pipeReader.ReadLine()) -notmatch 'QUIT') { $disp='write-host '+$msg+';'; invoke-expression($disp); $npipeServer.Disconnect(); $npipeServer.WaitForConnection(); }; } Finally { $npipeServer.Dispose(); }" 2>NUL
SET /A LOCALV_TRY=20 >NUL
:LaunchPowerShellSubProcess_WaitForPipe
powershell -nop -c "& {sleep -m 50}"
SET /A LOCALV_TRY=!LOCALV_TRY! - 1 >NUL
IF NOT "!LOCALV_TRY!" == "0" cmd /C "ECHO -NoNewLine|MORE 1>\\.\pipe\PowerShellCon_!LOCALV_PID!" 2>NUL || GOTO:LaunchPowerShellSubProcess_WaitForPipe
IF "!LOCALV_TRY!" == "0" EXIT /B 1
EXIT /B 0
Link to my original answer on the same topic.
