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Batch Script – Comments ”; Previous Next It’s always a good practice to add comments or documentation for the scripts which are created. This is required for maintenance of the scripts to understand what the script actually does. For example, consider the following piece of code which has no form of comments. If any average person who has not developed the following script tries to understand the script, it would take a lot of time for that person to understand what the script actually does. ECHO OFF IF NOT “%OS%”==”Windows_NT” GOTO Syntax ECHO.%* | FIND “?” >NUL IF NOT ERRORLEVEL 1 GOTO Syntax IF NOT [%2]==[] GOTO Syntax SETLOCAL SET WSS= IF NOT [%1]==[] FOR /F “tokens = 1 delims = ” %%A IN (”ECHO.%~1”) DO SET WSS = %%A FOR /F “tokens = 1 delims = ” %%a IN (”NET VIEW ^| FIND /I “\%WSS%””) DO FOR /F “tokens = 1 delims = ” %%A IN (”NBTSTAT -a %%a ^| FIND /I /V “%%a” ^| FIND “<03>””) DO ECHO.%%a %%A ENDLOCAL GOTO:EOF ECHO Display logged on users and their workstations. ECHO Usage: ACTUSR [ filter ] IF “%OS%”==”Windows_NT” ECHO Where: filter is the first part of the computer name^(s^) to be displayed Comments Using the Rem Statement There are two ways to create comments in Batch Script; one is via the Rem command. Any text which follows the Rem statement will be treated as comments and will not be executed. Following is the general syntax of this statement. Syntax Rem Remarks where ‘Remarks’ is the comments which needs to be added. The following example shows a simple way the Rem command can be used. Example @echo off Rem This program just displays Hello World set message=Hello World echo %message% Output The above command produces the following output. You will notice that the line with the Rem statement will not be executed. Hello World Comments Using the :: Statement The other way to create comments in Batch Script is via the :: command. Any text which follows the :: statement will be treated as comments and will not be executed. Following is the general syntax of this statement. Syntax :: Remarks where ‘Remarks’ is the comment which needs to be added. The following example shows the usage of the “::” command. Example @echo off :: This program just displays Hello World set message = Hello World echo %message% Output The above command produces the following output. You will notice that the line with the :: statement will not be executed. Hello World Note − If you have too many lines of Rem, it could slow down the code, because in the end each line of code in the batch file still needs to be executed. Let’s look at the example of the large script we saw at the beginning of this topic and see how it looks when documentation is added to it. ::=============================================================== :: The below example is used to find computer and logged on users :: ::=============================================================== ECHO OFF :: Windows version check IF NOT “%OS%”==”Windows_NT” GOTO Syntax ECHO.%* | FIND “?” >NUL :: Command line parameter check IF NOT ERRORLEVEL 1 GOTO Syntax IF NOT [%2]==[] GOTO Syntax :: Keep variable local SETLOCAL :: Initialize variable SET WSS= :: Parse command line parameter IF NOT [%1]==[] FOR /F “tokens = 1 delims = ” %%A IN (”ECHO.%~1”) DO SET WSS = %%A :: Use NET VIEW and NBTSTAT to find computers and logged on users FOR /F “tokens = 1 delims = ” %%a IN (”NET VIEW ^| FIND /I “\%WSS%””) DO FOR /F “tokens = 1 delims = ” %%A IN (”NBTSTAT -a %%a ^| FIND /I /V “%%a” ^| FIND “<03>””) DO ECHO.%%a %%A :: Done ENDLOCAL GOTO:EOF :Syntax ECHO Display logged on users and their workstations. ECHO Usage: ACTUSR [ filter ] IF “%OS%”==”Windows_NT” ECHO Where: filter is the first part of the computer name^(s^) to be displayed You can now see that the code has become more understandable to users who have not developed the code and hence is more maintainable. Print Page Previous Next Advertisements ”;