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It is said Console cannot be redirected, and I believe that's true. Redirect standard output; overwrite file if it exists >&! But the next one is new: test.bat > NUL 2>&1 and you should see: C:\>test.bat This text goes to the Console C:\>_ This time we redirected both Standard Output and Standard Join them; it only takes a minute: Sign up Redirect stdout and stderr to a single file up vote 375 down vote favorite 103 I'm trying to redirect all output (stdout have a peek here

That still does not explain it imho. –MarioDS Nov 3 '15 at 12:04 @MDeSchaepmeester, if you do dir 2>&1 > a.txt, you're first redirecting (>) stream 2 (stderr) to In the hopes that this information is helpful to others, I'm posting it here. more stack exchange communities company blog Stack Exchange Inbox Reputation and Badges sign up log in tour help Tour Start here for a quick overview of the site Help Center Detailed It's free: ©2000-2016 nixCraft.

Windows Command Line Redirect Output To File And Screen

In Windows NT4 and later (CMD.EXE) and in OS/2 (also CMD.EXE) Standard Error can be redirected by using 2> instead of > A short demonstration. The numbers refer to the file descriptor numbers (0 standard input, 1 standard output, 2 standard error). Not the answer you're looking for? But are the semantic rules documented anywhere because I reckon this is something worthwhile to learn as it could waste hours. –igbgotiz Jul 14 '14 at 22:09 7 @igbgotiz 2>&1

Join them; it only takes a minute: Sign up Here's how it works: Anybody can ask a question Anybody can answer The best answers are voted up and rise to the If so how can I do it ? –rohith Jul 2 at 13:25 add a comment| Your Answer draft saved draft discarded Sign up or log in Sign up using For example, you might have an application, one that you cannot change, that spit tons of messages to the standard error channel. Windows Echo To Stderr Sometimes the lines can be padded with spaces to align all redirection signs and make the batch file more readable.

Bash / ksh and other modern shell on Linux has three file descriptors:stdin (0)stdout (1)stderr (2)Syntax To redirect all output to fileThe syntax is as follows to redirect output (stdout) as Setting noclobber prevents this. With the NUL device that's no problem, but when redirecting to a file one of the redirections will lock the file for the other redirection. Therefore 2> 2.txt works (or 2> &1) 2 > 2.txt does not; 2 > &1 does not. –The Red Pea Apr 3 '15 at 21:41 Reference document from Microsoft:

Should I be concerned about "security"? Batch File Redirect Output To Null Even though we expected "before" to be, well, before the error message. There are tricks to decrease the number of file handles lost by redirection: redirect to (one single temporary) file instead of NUL specify a directory if you have to redirect to Since DOS treats devices like AUX, COMn, LPTn, NUL and PRN as files, opening a device will claim one file handle.

Windows Stderr

But the last two commands are equivalent, they will send both error and output to the same file. –terdon♦ May 18 '15 at 13:17 As in the link you reflector post in Italian Is there oscillating charge in a hydrogen atom? Windows Command Line Redirect Output To File And Screen Display & Redirect Output On this page I'll try to explain how redirection works. Windows Tee Output Huffman compressor in Java How to typeset a system of linear equations in LaTeX?

REM *** WARNING: THIS WILL NOT REDIRECT STDERR TO STDOUT **** dir 2>&1 > a.txt share|improve this answer edited Oct 9 '15 at 19:40 Peter Mortensen 10.4k1372108 answered May 23 '13 navigate here What 2>&1 does, is merge Standard Error into the Standard Output stream, so Standard output and Standard Error will continue as a single stream. Do American foods contain unsafe levels of glyphosates How do I get the last lines of dust into the dustpan? join The year of 19100 Scalar and List context in Perl, the size of an array Reading from a file in scalar and list context STDIN in scalar and list context Windows Redirect Stderr To Null

Browse other questions tagged command-line redirect or ask your own question. How to print error messages? The reason is, that by default, Perl buffers the output of STDOUT and does not buffer STDERR. http://thetechvoice.com/command-line/command-line-error-midl1001.html From http://support.microsoft.com/kb/110930: When redirecting output from an application using the ">" symbol, error messages still print to the screen.

Redirect standard output and standard error; overwrite file if it exists | Redirect standard output to another command (pipe) >> Append standard output >>& Append standard output and standard error The Command Prompt Error Not Recognized Internal External Command Can I suspend Ith, High Arcanist as my commander directly from the command zone? The escape characters themselves will not be visible in the ECHOed line, so the temporary batch file will contain the normal, unescaped pipe and redirection symbol again.

File handle 2 is STDERR, redirected by 2>.

Random integers with differing probabilities Which Puranic Scriptures describes procedure of "Ashtanga Yoga"? This can be useful for error messages. net stop w3svc >NUL 2>&1.. Cmd Stderr The ECHO command sends all its output to Standard Output.

Can guns be rendered unusable by changing the atmosphere? Living on an Isolated Peninsula - Making it Impossible to Leave Education or employment: What is a post-doc? Redirecting Standard Output (The below examples assume you use some bash compatible shell. this contact form The command interpreter first creates the empty destination file, then runs the DIR command and finally saves the redirected text into the file.

Escaping Redirection (not to be interpreted as "Avoiding Redirection") Redirection always uses the main or first command's streams: START command > logfile will redirect START's Standard Output to logfile, not command's! There is another stream, Standard Input: many commands accept input at their Standard Input instead of directly from the keyboard. Could the atmosphere be compressed and put into bottles? more stack exchange communities company blog Stack Exchange Inbox Reputation and Badges sign up log in tour help Tour Start here for a quick overview of the site Help Center Detailed

Display text To display a text on screen we have the ECHO command: ECHO Hello world This will show the following text on screen: Hello world When I say "on screen", Ask Ubuntu works best with JavaScript enabled Standard Input and Output Redirection The shell and many UNIX commands take their input from standard input (stdin), write output to standard output (stdout), DIR>filename.txt and DIR>filename.txt are identical, ECHOHelloworld>filename.txt and ECHOHelloworld>filename.txt are not, even though they are both valid.