Batch programming; Script writes to a file which writes to a file

I have a script I run when reinstalling Windows. It creates a script called login.cmd which is executed via task manager when the user logs in.

Since the primary script writes the login.cmd file based on the users preferences and custom installation it is different for each user. That part is fine.

What I'm trying to accomplish is the have the login.cmd script write log file entries so I can debug the login.cmd and track its execution.

This will write a command to login.cmd

Code:

Echo IF EXIST C:\ABC\XYZ\*.tmp DEL C:\ABC\XYZ\*.tmp /f/s >>C:\TOOL\LOGIN.CMD

.
But what I want to have in the login.cmd is

Code:

IF EXIST C:\ABC\XYZ\*.tmp DEL C:\ABC\XYZ\*.tmp /f/s >>%LOCALAPPDATA%\Temp\Login.log 2>&1

I can't write this in the initial script;

Code:

Echo IF EXIST C:\ABC\XYZ\*.tmp DEL C:\ABC\XYZ\*.tmp /f/s >>%LOCALAPPDATA%\Temp\Login.log 2>&1 >>C:\TOOL\LOGIN.CMD

as it crashes the script.

How to I get the log file redirect into the login.cmd using the echo statement in the primary script?

While you can learn the proper escape sequences for CMD, it's a time waster for overly complicated lines like yours.

The simple solution is two-fold:
1. Wrap a complicated expression inside a variable, which (mostly) treats it as a literal line. The exception is you need to escape existing "%var%" expressions with "%%var%%".

2. Use delayed expansion, so CMD isn't doing variable expansion on the fly.

Code:

@echo off
setlocal enabledelayedexpansion

REM Escape %LOCALAPPDATA% with %%LOCALAPPDATA%%

set "line=IF EXIST C:\ABC\XYZ\*.tmp DEL C:\ABC\XYZ\*.tmp /f/s >>%%LOCALAPPDATA%%\Temp\Login.log 2>&1"
echo !line! >> login.cmd

login.cmd

Code:

IF EXIST C:\ABC\XYZ\*.tmp DEL C:\ABC\XYZ\*.tmp /f/s >>%LOCALAPPDATA%\Temp\Login.log 2>&1

Try3 said:

You'll need to learn about escape characters

Well that was embarrassingly simple.

Code:

Echo IF EXIST C:\ABC\XYZ\*.tmp DEL C:\ABC\XYZ\*.tmp /f/s ^>^>%LOCALAPPDATA%\Temp\Login.log 2^>^&1 >>C:\TOOLS\LOGIN.CMD

thanks for your help.

Sorry @garlin I saw your response after @Try3 response.

"Overly complicated"? Lol. I have much more complicated code than that in the script.

Code:

DISM.exe /Online /Add-ProvisionedAppxPackage /PackagePath:Microsoft.HEVCVideoExtension_2.0.61931.0_neutral__8wekyb3d8bbwe.appxbundle /DependencyPackagePath:Microsoft.VCLibs.140.00_14.0.32530.0_x64__8wekyb3d8bbwe.Appx /DependencyPackagePath:Microsoft.VCLibs.140.00_14.0.32530.0_x86__8wekyb3d8bbwe.Appx /skiplicense >>%LogFile% 2>&1

As I used to ask PaulBlack, who was fond of asking how to escape long complicated expressions, which is more readable (for debugging)? Something that resembles the original command, or something with a bajillion escape characters?

garlin said:

As I used to ask PaulBlack, who was fond of asking how to escape long complicated expressions, which is more readable (for debugging)? Something that resembles the original command, or something with a bajillion escape characters?

Indeed. I've often been challenged to the point of tearing my hair out trying to find unbalanced ", % or ( ) in the script.