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How to create batch file without mistakes

Do you want to create batch file without any mistakes and make it really useful? This article will teach you how do it.
Is it possible to make changes in Windows registry using batch files?
It seems that the simplest way here to make changes in Windows registry is to use REG files. These are special text files that function in Windows for making necessary Windows registry changes without searching long for the key in the tree shown by RegEdit. As I see it, the matter goes about making batch changes in the case you can manage without BAT files at all: you may write several registry keys into one REG file and the keys will be changed while REG file is launched. But if you need to generate registry keys dynamically, BAT file can perform REG file generating and launching. The only question is how to create batch file.
REG-files have a simple format. In fact it is a text file written as follows:
[HKEY_LOCAL_MACHINESub1Sub2]
“Par1″=dword:0
“Par2″=”string”
“Par3″=hex:cc,1b,00,00,00,40,3d,68
Here, it’s obvious, instead of lines in brackets you should put the real path to the branch in registry which parameters you are intend to change (do not omit brackets). The names of these parameters should be quoted and the same for their values, in case of line parameters. For DWORD and HEX parameters, as in example, write its type and put colon after equals in the line. Do not separate the values somehow – changes in parameters, starting with a new line in brackets, will be made to a new address. At the beginning of the file put the line “Windows Registry Editor Version 5.00” (without quotation marks) – this line is necessary for the Registry Editor to determine whether this file includes the keys for making registry changes – it is very important to include them into REG files. Also, do not forget to name the extension of the output file as .REG.
To compose the file use “>>” – command. That is a standard way to convert BAT file data into a text file. For making changes in the registry you use regedit utility in which REG file’s name should be used as a parameter, for example, “regedit crack.reg” (without quotation marks).
Why is there no percentage mark in the line seen on the screen?
In batch files percentage mark is used to indicate variables, or variable environments, or internal variables of the BAT-file. So, if you’d like to see percentage mark on the screen, you just need to use it twice: for example, “echo This day performed 0.25%% of the whole project”. By the way, is not the only symbol that has a special meaning in BAT files. Such symbols also include “>”, “<", etc. They can be displayed on the screen with the help of combinations "^<", "^>” (i.e. you put a tick before the symbol).
What is errorlevel?
Sooner or later every batch files creator faces the problem of checking the result of one command execution before executing the other one. For that we have built-in variable “errorlevel” that changes its value after each command execution. Its value can vary for different commands used in batch files. Usually successful execution of the command is displayed as zero value of variable, but not always other value implies any errors. So if create batch file, you should remember about this meaning of errorlevel.
This variable is used as follows:
if errorlevel 0 echo Errorlevel is 0 or greater
Instead of “echo Errorlevel is 0 or greater” you can put any necessary command. After “if” you can add “not” (no quotation marks for this time again) – then the value becomes diametrically opposed. It should be mentioned that “errorlevel N”-construction does not mean precise equality of variable “errorlevel” to value N. It means that the command will be executed only in case “errorlevel” value is or is greater than N. Thus it is more convenient to check errors with the help of “if errorlevel” -construction than to execute the command successfully. But if you write “if not errorlevel 1”, that means in case “errorlevel” is nonnegative, we obtain the result of “errorlevel” equal to zero. Unfortunately nonnegative values of this variable are not guaranteed. For more details you can read about “if errorlevel” -construction in Windows help manual.
To learn more please visit http://www.drbatcher.com .

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