check error code dos
stdin, stdout, stderr Part 5 – If/Then Conditionals Part 6 – Loops Part 7 – Functions Part 8 – Parsing Input Part 9 – Logging Part 10 – Advanced dos error code 9009 Tricks Today we’ll cover return codes as the right way to communicate the
Dos Error Code 128outcome of your script’s execution to the world. Sadly, even skilled Windows programmers overlook the importance of return codes. Return Code
Dos Error Code 255Conventions By convention, command line execution should return zero when execution succeeds and non-zero when execution fails. Warning messages typically don’t effect the return code. What matters is did the script work or not?
Dos Error Code 1Checking Return Codes In Your Script Commands The environmental variable %ERRORLEVEL% contains the return code of the last executed program or script. A very helpful feature is the built-in DOS commands like ECHO, IF, and SET will preserve the existing value of %ERRORLEVEL%. The conventional technique to check for a non-zero return code using the NEQ (Not-Equal-To) operator of the IF command: IF %ERRORLEVEL% NEQ 0 ( REM do dos error codes list something here to address the error ) Another common technique is: IF ERRORLEVEL 1 ( REM do something here to address the error ) The ERRORLEVEL 1 statement is true when the return code is any number equal to or greater than 1. However, I don’t use this technique because programs can return negative numbers as well as positive numbers. Most programs rarely document every possible return code, so I’d rather explicity check for non-zero with the NEQ 0 style than assuming return codes will be 1 or greater on error. You may also want to check for specific error codes. For example, you can test that an executable program or script is in your PATH by simply calling the program and checking for return code 9009. SomeFile.exe IF %ERRORLEVEL% EQU 9009 ( ECHO error - SomeFile.exe not found in your PATH ) It’s hard to know this stuff upfront – I generally just use trial and error to figure out the best way to check the return code of the program or script I’m calling. Remember, this is duct tape programming. It isn’t always pretty, but, it gets the job done. Conditional Execution Using the Return Code There’s a super cool shorthand yo
task. Batch file decisions may be made based on what code was generated. This webpage gives a short discussion of these codes and ways in which they might be used. Deep dos beep codes detail will not be gone into. If you want to know more, see your DOS unix error code manual and/or the On-Screen Help. Be aware that not everything presented here may work as shown for the commands included with the windows error code version or manufacturer of DOS you have. INFORMATION BELOW MAY NOT BE REPRODUCED WITHOUT PERMISSION FROM THE AUTHOR © What are Exit Codes? When DOS or its software finishes a command operation, it usually generates a http://steve-jansen.github.io/guides/windows-batch-scripting/part-3-return-codes.html code upon exiting. When it gives that exit code, it is essentially saying: Here are the results of my work. Since these are generated after a command has finished and exited, they are known as "Exit Codes". These codes are hidden from the user but may be tested for via various methods. The codes give the computer system an idea of what happened during an operation or after it has completed. One code might signal http://www.chebucto.ns.ca/~ak621/DOS/ExitCode.html that the task ended with no errors, or that it ended with no errors but that the operation was not successful. If an error did occur, a code might be generated depending on what the error was. Why Might I Want to Use Exit Codes? Since these codes can indicate what happened during a computer operation, they can be used in a batch file to tailor the direction of further procedures. So as an example, if one used the "FC" (File Compare) command and the outcome was that two files matched, a further procedure could be that the batch file be directed to delete one of the duplicate files. Another example of this is given farther on. (See this website's Batch File Tutorial for information on writing batch files.) What do Exit Codes Look Like? Each is one of 256 available values represented by a number from 0 (zero) through 255. `0' typically represents an operation that was completed with no errors. Other numbers might represent problems or various results. Note that not all available numbers will typically be used by a program. In fact, I know of only a few commands or programs that do use all numbers. In addition, there are also those that are programmed to generate random, meaningless numbers upon completion. They only generate one of these at a tim
here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and http://superuser.com/questions/194662/how-to-check-the-exit-code-of-the-last-command-in-batch-file policies of this site About Us Learn more about Stack Overflow the company Business Learn more about hiring developers or posting ads with us Super User Questions Tags Users Badges Unanswered Ask Question _ Super User is a question and answer site for computer enthusiasts and power users. Join them; it only takes a minute: Sign up Here's how it works: error code Anybody can ask a question Anybody can answer The best answers are voted up and rise to the top How to check the exit code of the last command in batch file? up vote 54 down vote favorite 5 Inside a batch file on Windows, I use 7-zip like this: ...\right_path\7z a output_file_name.zip file_to_be_compressed How could I check the exit code of dos error code 7z and take the appropriate action ? windows-xp batch share|improve this question asked Oct 1 '10 at 4:47 Misha Moroshko 1,63861628 1 Also asked on Stackoverflow: How do I get the application exit code from a Windows command line? –Deanna Jun 24 '13 at 11:42 add a comment| 2 Answers 2 active oldest votes up vote 62 down vote accepted Test for a return code greater than or equal to 1: if ERRORLEVEL 1 echo Error or if %ERRORLEVEL% GEQ 1 echo Error or test for a return code equal to 0: if %ERRORLEVEL% EQU 0 echo OK You can use other commands such as GOTO where I show echo. share|improve this answer edited Oct 1 '10 at 5:27 answered Oct 1 '10 at 4:58 Dennis Williamson 57.4k10100135 I tried your code. I got the following error: 0 was unexpected this time. –Misha Moroshko Oct 1 '10 at 5:13 2 @Misha: You may have tried it with the percent signs the way I originally posted it. Try it without them or try the other versions I added. –Dennis Williamson