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How do I make a Windows batch script completely silent?

There has been variants of this question asked for generations, but despite writing some quite complicated Windows scripts, I can't seem to find out how to make them actually silent.

The following is an excerpt from one of my current scripts:

@ECHO OFF SET scriptDirectory=%~dp0 COPY %scriptDirectory%test.bat %scriptDirectory%test2.bat FOR /F %%f IN ('dir /B "%scriptDirectory%*.noext"') DO ( del "%scriptDirectory%%%f" ) ECHO 

The result of this is:

C:\Temp> test.bat         1 file(s) copied. File Not Found Echo is off.  C:\Temp> 

Whereas the "1 file(s) copied." is just annoying, the "File Not Found" makes the user think that something has gone wrong (which it hasn't - no files is fine).

like image 359
Mike Sadler Avatar asked Feb 04 '13 12:02

Mike Sadler


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Example# @echo off prevents the prompt and contents of the batch file from being displayed, so that only the output is visible. The @ makes the output of the echo off command hidden as well.

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2 Answers

To suppress output, use redirection to NUL.

There are two kinds of output that console commands use:

  • standard output, or stdout,

  • standard error, or stderr.

Of the two, stdout is used more often, both by internal commands, like copy, and by console utilities, or external commands, like find and others, as well as by third-party console programs.

>NUL suppresses the standard output and works fine e.g. for suppressing the 1 file(s) copied. message of the copy command. An alternative syntax is 1>NUL. So,

COPY file1 file2 >NUL 

or

COPY file1 file2 1>NUL 

or

>NUL COPY file1 file2 

or

1>NUL COPY file1 file2 

suppresses all of COPY's standard output.

To suppress error messages, which are typically printed to stderr, use 2>NUL instead. So, to suppress a File Not Found message that DEL prints when, well, the specified file is not found, just add 2>NUL either at the beginning or at the end of the command line:

DEL file 2>NUL 

or

2>NUL DEL file 

Although sometimes it may be a better idea to actually verify whether the file exists before trying to delete it, like you are doing in your own solution. Note, however, that you don't need to delete the files one by one, using a loop. You can use a single command to delete the lot:

IF EXIST "%scriptDirectory%*.noext" DEL "%scriptDirectory%*.noext" 
like image 80
Andriy M Avatar answered Oct 12 '22 14:10

Andriy M


If you want that all normal output of your Batch script be silent (like in your example), the easiest way to do that is to run the Batch file with a redirection:

C:\Temp> test.bat >nul 

This method does not require to modify a single line in the script and it still show error messages in the screen. To supress all the output, including error messages:

C:\Temp> test.bat >nul 2>&1 

If your script have lines that produce output you want to appear in screen, perhaps will be simpler to add redirection to those lineas instead of all the lines you want to keep silent:

@ECHO OFF SET scriptDirectory=%~dp0 COPY %scriptDirectory%test.bat %scriptDirectory%test2.bat FOR /F %%f IN ('dir /B "%scriptDirectory%*.noext"') DO ( del "%scriptDirectory%%%f" ) ECHO REM Next line DO appear in the screen ECHO Script completed >con 

Antonio

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Aacini Avatar answered Oct 12 '22 13:10

Aacini