Error Output Linux
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12, 2008 in BASH Shell, Linux, UNIXQ. How do I redirect stderr to stdout? How do I redirect stderr to a file? A. Bash and
Linux Output Error To File
other modern shell provides I/O redirection facility. There are 3 default standard linux error output to dev null files (standard streams) open: [a] stdin - Use to get input (keyboard) i.e. data going into a program.
Linux Error Output Redirect To File
[b] stdout - Use to write information (screen)[c] stderr - Use to write error message (screen)Understanding I/O streams numbersThe Unix / Linux standard I/O streams with numbers:HandleNameDescription0 stdin Standard input1 linux pipe error output to file stdout Standard output2 stderr Standard errorRedirecting the standard error stream to a fileThe following will redirect program error message to a file called error.log: $ program-name 2> error.log
$ command1 2> error.logRedirecting the standard error (stderr) and stdout to fileUse the following syntax: $ command-name &>file OR $ command > file-name 2>&1 Another useful example: # find /usr/home -name .profile linux pipe standard error 2>&1 | moreRedirect stderr to stdoutUse the command as follows: $ command-name 2>&1 Share this tutorial on:TwitterFacebookGoogle+Download PDF version Found an error/typo on this page?About the author: Vivek Gite is a seasoned sysadmin and a trainer for the Linux/Unix & shell scripting. Follow him on Twitter. OR read more like this:How do I save or redirect stdout and stderr into different files?Linux Redirect Error Output To FileBASH Shell Redirect Output and Errors To /dev/nullUnix and Linux: Redirect Error Output To null CommandPrinting output of c program to a file in LinuxUnix / Linux: Save Output To FilePython Run External Command And Get Output On Screen or In VariablePython Execute Unix / Linux Command ExamplesLinux / Unix Find Command: Avoid Permission Denied MessagesHow to gzip and keep original file on Unix or Linux command line{ 11 comments… add one } Sayed Ahmad February 12, 2012, 12:11 amWhat this mean? $ command > file-name 2>&1 Reply Link Hesham M January 22, 2014, 3:34 pmThis means redirect stdout to file-name, with that in mind redirect stderr t stdout. This will lead to b
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Linux Redirect Stderr And Stdout To File
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Linux Redirect Stderr And Stdout To Null
Badges Unanswered Ask Question _ Unix & Linux Stack Exchange is a question and answer site for users of Linux, FreeBSD and other Un*x-like operating systems. Join them; it only http://www.cyberciti.biz/faq/redirecting-stderr-to-stdout/ 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 top Always redirect error to /dev/null up vote 12 down vote favorite 3 I know I can redirect the error messages from a command to /dev/null using the following syntax: command arg1 arg2 2>/dev/null But http://unix.stackexchange.com/questions/75616/always-redirect-error-to-dev-null is there a way to do this by default so that the error messages always go to /dev/null, unless I specify otherwise? command-line io-redirection share|improve this question asked May 13 '13 at 7:35 Richard 4461315 1 In short: yes - redirect /dev/stderr to /dev/null. But, if you can't figure it out on your own, you shouldn't try, as you are more likely to break something fatally than succeed. –Benubird May 13 '13 at 8:11 @Benubird stderr != /dev/stderr. Redirecting that file won't do anything. The file in /dev/ is just for convenience. –Chris Down May 14 '13 at 3:51 @ChrisDown you're right, /dev/stderr is just a link. Still, a lot of processes write to that instead of fd/2, which you could also redirect. It gets more complicated from there - which is why I left a comment instead of an answer :). –Benubird May 14 '13 at 8:11 add a comment| 1 Answer 1 active oldest votes up vote 17 down vote Lots of programs send output to stderr that isn't actually indicative of errors. For example, in some
here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and http://stackoverflow.com/questions/6674327/redirect-all-output-to-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 Stack Overflow Questions Jobs Documentation Tags http://askubuntu.com/questions/625224/how-to-redirect-stderr-to-a-file Users Badges Ask Question x Dismiss Join the Stack Overflow Community Stack Overflow is a community of 4.7 million programmers, just like you, helping each other. Join them; it only error output takes a minute: Sign up Redirect all output to file [duplicate] up vote 468 down vote favorite 143 This question already has an answer here: How can I redirect and append both stdout and stderr to a file with Bash? 6 answers I know that in Linux, to redirect output from the screen to a file, I can either use the linux redirect stderr > or tee. However, I'm not sure why part of the output is still output to the screen and not written to the file. Is there a way to redirect all output to file? linux bash io-redirection share|improve this question edited Mar 3 '15 at 15:42 R O M A N I A 12.4k116675 asked Jul 13 '11 at 5:06 Rayne 3,28182533 marked as duplicate by fedorquilinux Users with the linux badge can single-handedly close linux questions as duplicates and reopen them as needed. Jun 7 at 11:44 This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question. add a comment| 10 Answers 10 active oldest votes up vote 721 down vote accepted That part is written to stderr, use 2> to redirect it. For example: foo > stdout.txt 2> stderr.txt or if you want in same file: foo > allout.txt 2>&1 Note: this works in (ba)sh, check your shell for proper syntax share|improve this answer answered Jul 13 '11 at 5:10 Op De Cirkel 15.8k5
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 answers to any questions you might have Meta Discuss the workings and policies of this site About Us Learn more about Stack Overflow the company Business Learn more about hiring developers or posting ads with us Ask Ubuntu Questions Tags Users Badges Unanswered Ask Question _ Ask Ubuntu is a question and answer site for Ubuntu users and developers. 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 top How to redirect stderr to a file up vote 8 down vote favorite 1 While using nohup to put a command to run in background some of content appear in terminal. cp: error reading ‘/mnt/tt/file.txt’: Input/output error cp: failed to extend ‘/mnt/tt/file.txt’: Input/output error I want to save that content to a file. command-line redirect share|improve this question edited May 18 '15 at 13:42 asked May 18 '15 at 12:31 André M. Faria 3961618 add a comment| 1 Answer 1 active oldest votes up vote 14 down vote accepted There are two main output streams in Linux (and other OSs), standard output (stdout)and standard error (stderr). Error messages, like the ones you show, are printed to standard error. The classic redirection operator (command > file) only redirects standard output, so standard error is still shown on the terminal. To redirect stderr as well, you have a few choices: Redirect stderr to another file: command > out 2>error Redirect stderr to stdout (&1), and then redirect stdout to a file: command >out 2>&1 Redirect both to a file: command &> out For more information on the various control and redirection operators, see here. share|improve this answer answered May 18 '15 at 12:50 terdon♦ 42k686153 So 'hashdeep -rXvvl -j 30 -k checksums.txt /mnt/app/ >> result_hashdeep.txt 2> error_hashdeep.txt &' or 'hashdeep -rXvvl -j 30 -k checksums.txt /mnt/app/ >> result_hashdeep.txt 2>&1' or 'hashdeep -rXvvl -j 30 -k checksums.txt /mnt/app/ &> result_mixed.txt' –André M. Faria May 18 '15 at 12:59 1 @AndréM.Faria yes. 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 provided, I could use |& instead of 2>&1 they are equivalent, thanks for you time. –André M. Faria May 18 '15 at 13:38 @terdon how do I redirect output to a file which has no "w" permission for others , I meant to ask can I redirect using sudo ? If so how can I do it