Bash and other modern shell provides I/O redirection facility. up vote 92 down vote favorite 20 I know this much: $ command 2>> error $ command 1>> output Is there any way I can output the stderr to the error Both ways are 'logrotateable'. ls -lR > dir-tree.list # Creates a file containing a listing of the directory tree. : > filename # The > truncates file "filename" to zero length. # If file not Source
i>&j # Redirects file descriptor i> to j. # All output of file pointed to by i gets sent to file pointed to by j. >&j # When Bash creates a child process, as with exec, the child inherits fd 5 (see Chet Ramey's archived e-mail, SUBJECT: RE: File descriptor 5 is held open). Is the ability to finish a wizard early a good idea? Reply Link Matt Kukowski January 29, 2014, 6:33 pm In pre-bash4 days you HAD to do it this way: cat file > file.txt 2>&1 now with bash 4 and greater versions… http://www.tldp.org/LDP/abs/html/io-redirection.html
There are two incorrect concepts in your answer. What to do with my pre-teen daughter who has been out of control since a severe accident? The classic redirection operator (command > file) only redirects standard output, so standard error is still shown on the terminal. The numbers refer to the file descriptor numbers (0 standard input, 1 standard output, 2 standard error).
I prefer separate files which require less parsing but as I said, whatever makes your boat floating :) –quizac Dec 8 '14 at 11:02 how do you switch back good explanation, I'd like to make a function on C that redirects STDIN and SDTOUT to an script, how can I do that, I mean, the exist a library's on C Logical && statement with null validation Are there other Pokemon with higher spawn rates right now? Ambiguous Output Redirect Search for "shell redirection" for more details. –Mat Mar 17 at 5:04 add a comment| up vote 119 down vote The simplest syntax to redirect both is: command &> logfile If
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 Bash Redirect Stdout And Stderr To Dev Null exec 3>&1 # Save current "value" of stdout. How to slow down sessions? http://www.tldp.org/LDP/abs/html/io-redirection.html It almost work, but not from xinted ;( share|improve this answer answered Apr 23 '09 at 13:14 log-control I'm guessing it doesn't work because of "/dev/fd/3 Permission denied".
Reply Link TodorMinchev May 14, 2013, 9:03 pm RudyD +1 :) Reply Link Daniel August 26, 2013, 7:22 pm Actually it means "first redirect STDERR to STDOUT, so any errors printed Bash Write To Stderr Just something to keep in mind. no longer refers to the exit status of do_something, but the exit status of tee. –Flimm Jan 20 '15 at 14:09 | show 3 more comments up vote 124 down vote The Last Monday Could IOT Botnets be Stopped by Static IP addressing the Devices?
The form of a command with standard input and output redirection is: $ command -[options] [arguments] < input file > output file Redirection may fail under some circumstances: 1) if you http://sc.tamu.edu/help/general/unix/redirection.html Would it be ok to eat rice using spoon in front of Westerners? Redirect Stderr To Dev Null Follow him on Twitter. Bash Redirect Stderr To Dev Null New employee has offensive Slack handle due to language barrier What are the differences between update and zip packages Modo di dire per esprimere "parlare senza tabù" What is a word
The accepted answer do_something &>filename doesn't. +1. –Withheld Jan 4 '13 at 16:01 4 @Daniel, but this question is specifically about bash –John La Rooy Aug 19 '13 at 3:38 http://supercgis.com/redirect-stderr/redirecting-standard-error-unix.html Browse other questions tagged command-line redirect or ask your own question. Modo di dire per esprimere "parlare senza tabù" How to search for flights for a route staying within in an alliance? It does appear to be working on my machine which runs Gnu bash v3.2.48. –James Wald Apr 10 '14 at 7:32 5 @CostiCiudatu the &>> operator does not seem to Bash Pipe Stderr
share|improve this answer answered Apr 23 '13 at 5:07 einstein6 192 add a comment| up vote 1 down vote "Easiest" way (bash4 only): ls * 2>&- 1>&-. Are C++14 digit separators allowed in user defined literals? You can even combine sudo to downgrade to a log user account and add date's subject and store it in a default log directory :) Reply Link Alejandro April 22, 2015, have a peek here Faria May 18 '15 at 12:59 1 @AndréM.Faria yes.
share|improve this answer edited Oct 7 '10 at 5:44 David Johnstone 14.1k115568 answered Mar 12 '09 at 9:17 dirkgently 74.6k1294163 6 Somebody should restore to the second edit of this Csh Redirect Stderr 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 Accidentally modified .bashrc and now I cant login despite entering password correctly What happens if the same field name is used in two separate inherited data templates?
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 You can also use 1 instead of 2 so that stdout gets redirected to the 'file' share|improve this answer answered Sep 24 '11 at 5:53 PaulDaviesC 512922 add a comment| Your Basically you can: redirect stdout to a file redirect stderr to a file redirect stdout to a stderr redirect stderr to a stdout redirect stderr and stdout to a file redirect Tee Stderr What are the difficulties of landing on an upslope runway What to do when majority of the students do not bother to do peer grading assignment?
To the author of the original post, It depends what you need to achieve. It is analogous to a file handle in C.Using file descriptor 5 might cause problems. By default, standard input is connected to the terminal keyboard and standard output and error to the terminal screen. http://supercgis.com/redirect-stderr/redirecting-standard-error-csh.html linux bash share|improve this question asked Oct 26 '11 at 10:36 user784637 4,0751958111 add a comment| 5 Answers 5 active oldest votes up vote 162 down vote accepted Just add them
Reusable Matrix block types Delayed effects after player's death How to leave a job for ethical/moral issue to a potential employer without explaining details Should I define the relations between tables Does catching/throwing exceptions render an otherwise pure method to be impure? Just for completion's sake, you can write 1> as just > since the default file descriptor is the output. Does bitcoin have the potential to be subject to a hard fork where miners are forced to choose which fork they will accept, like Etherum?
How to explain centuries of cultural/intellectual stagnation? Reply Link Security: Are you a robot or human? it cause original logfile is allways owerwritten. ls -yz 2>&1 >> command.log # Outputs an error message, but does not write to file. # More precisely, the command output (in this case, null) #+ writes to the file,
as you can see. Hot Network Questions How to adjust UI scaling for Chrome? So stderr goes to the stdout and that goes to the file. Bitwise rotate right of 4-bit value Print some JSON What to do when majority of the students do not bother to do peer grading assignment?
There are 3 default standard files (standard streams) open: [a] stdin - Use to get input (keyboard) i.e. Consider it a simplified type of file pointer. Limit Notation. Redirecting Code Blocks20.3.