There are three variations of the IF and IF NOT commands.
- IF EXIST: Execute the commandline only if a particular file exists:
IF EXIST some.txt COPY c:/some.dll %windir%/SYSTEM/some.dll
- Compare two text strings, and execute the commandline only if they are identical.
IF %HostWinBootDrv%==C SET WinDir=C:\WINDOWS
- Error testing: Check the exit code of the most recently run program. If it is equal to or greater than the number specified, execute the command:
IF ERRORLEVEL 4 ERASE trashfile.tmp /P
The better way to understand this command is try it yourself.
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