Windows Batch Processing : retry execution of commands

Sometimes while working with windows batch file, you want to re-execute steps if they fail. This can be achieved in many ways. In this post, I'll use a user defined variable, a built in ERRORLEVEL variable and batch labels to achieve the same.  

ERRORLEVEL is a built in DOS variable which is automatically set to 0 if the command executes successfully but there is a catch. In few operating systems, ERRORLEVEL can be set to a negative value if a command is unsuccessful. The ideal way to check and to direct the flow of command execution is by checking IF %ERRORLEVEL% NEQ 0 

Thanks to WebGuru’s Blog for this tip but script written by him wasn't working. 

The batch script is as follows :

 rem set a retry variable initially to 0  
 set retry=0  
   
 :step1  
 set step=1  
 @echo (%date%%time%) Step 1 : copying file  
   
 copy "C:\temp\file1" "E:\temp\file1"  
   
 @echo Errorlevel is %ERRORLEVEL%  
 if %ERRORLEVEL% NEQ 0 goto retry  
   
 rem re-set the retry number if success  
 set retry=0  
   
 :step2  
 set step=2  
 @echo (%date%%time%) Step 2 : moveing file  
   
 ren "E:\temp\file1" "E:\temp\file2"  
 @echo Errorlevel is %ERRORLEVEL%  
 if %ERRORLEVEL% NEQ 0 goto retry  
   
 rem re-set the retry number if success  
 set retry=0  
   
 :step3  
 set step=3  
 @echo (%date%%time%) Step 3 : delete previous file  
   
 rm "C:\temp\file1"  
   
 @echo Errorlevel is %ERRORLEVEL%  
 rem At the last step, direct the flow to the end of file otherwise it will execute retry block  
 if %ERRORLEVEL% EQU 0 goto eof  
 if %ERRORLEVEL% NEQ 0 goto retry  
   
 :retry  
   
 set /a retry=%retry%+1  
 @echo (%date% %time%) There was an error at STEP%step%, retrying again!  
 if %retry% LSS 6 (goto :step%step%)  
 if %retry% EQU 6 (goto :err)  
   
 :err  
 @echo (%date% %time%) sorry, this script stopped due to a few unsuccessful retries.  
 EXIT  
   
 :eof  
 @echo (%date% %time%) Success! The script completed successfully!  
 EXIT