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Bash Redirect Error To File


When sed starts to read the file, it contains nothing. These will be used as real terminal STDOUT and STDERR. 1> >(...) redirects STDOUT to command in parens parens(sub-shell) executes 'tee' reading from exec's STDOUT(pipe) and redirects to 'logger' command via ls -l 2>&1 >&3 3>&- | grep bad 3>&- # Close fd 3 for 'grep' (but not 'ls'). # ^^^^ ^^^^ exec 3>&- # Now close it for the remainder of Multiple redirections More redirection operations can occur in a line of course. http://onlinetvsoftware.net/bash-redirect/bash-redirect-error-to-log-file.php

There are other problems as well. I was looking for a solution for the following problem: I want to execute a shell script (both remotely via RSH and locally). If you write date= $(date) 2>/dev/null, the “command not found” message comes from the shell, not from the command whose error stream is redirected. exec also allow us to manipulate the file descriptors.

Redirect All Output To File Bash

The TARGET is truncated before writing starts. Is my workplace warning for texting my boss's private phone at night justified? Redirecting Code Blocks20.3. How do I redirect stderr to a file?

Under normal circumstances, there are 3 files open, accessible by the file descriptors 0, 1 and 2, all connected to your terminal: NameFDDescription stdin0standard input stream (e.g. On THE other hand or on another hand? Intuition behind Harmonic Analysis in Analytic Number Theory Did Donald Trump call Alicia Machado "Miss Piggy" and "Miss Housekeeping"? Bash Redirect Stdout And Stderr To Different Files for real loggin better way is: exec 1>>$LOG_FILE it cause log is allways appended. –Znik Dec 8 '14 at 9:43 2 That's true although it depends on intentions.

Is this safe to display MySQL query error in webpage if something went wrong? The second is less efficient but behaves in ways that are useful in certain circumstances. (Read about "subshells" to learn more.) –dubiousjim Oct 19 '12 at 14:20 add a comment| up Tagged with: error message, I/O redirection, keyboard, Linux, log program, program error, redirect stderr stdout to file, redirect stderr to file, redirect stdout to file, redirection, standard error, stderr, stdin, stdout, The second part of the problem is that the bash built-in "read" returns on a newline or the option of N chars or delimiter X –neither of which would be useful

command >/dev/null 2>&1 See also Internal: Illustrated Redirection Tutorial Internal: The noclobber option Internal: The exec builtin command Internal: Simple commands parsing and execution Internal: Process substitution syntax Internal: Obsolete and Bash Redirect Stdout And Stderr To Same File It will make STDERR point to STDOUT and then change STDOUT to something else (without touching STDERR) Here is a more detailed tutorial covering both those misconceptions http://wiki.bash-hackers.org/howto/redirection_tutorial Reply Link iek At that stage, you're not redirecting stderr anywhere. Do always put a space between each redirection, and between the argument list and the first redirect.

Bash Output To File

See also http://www.vincebuffalo.com/2013/08/08/the-mighty-named-pipe.html Real name: E-Mail: Website: Enter your comment. I'm very lost with this. Redirect All Output To File Bash Put '2>&1' after '>file.log' and it works. –Lars Wirzenius Mar 12 '09 at 9:25 1 Good point, I seem to have been doing this wrong all these years... Bash Redirect Stderr To File Append Here documents <

Anyway, many thanks again. )jack( R.W. check over here Though it might work, I'm not sure if you can expect all applications to behave correctly with a closed stderr. You can redirect the file descriptors of the shell permanently (or at least until the next time you change them) by using a redirection on the exec builtin with no command sorry for that : ( Here comes some additional tips. 0, 1, 2...9 are file descriptors in bash. 0 stands for stdin, 1 stands for stdout, 2 stands for stderror. 3~9 Bash Redirect Stderr To Stdout To File

Changing FD #1 doesn't affect FD #3 from now on. If I change in the 1st exec to append stdout to logfile (exec 3>&1 1>>logfile 2>&1) the result is correct: Hello World ls: filedoesnotexist: No such file or directory my message If you have already read a line of n, then after n>&m if you read a line from m, you will get the second line of the file. his comment is here Is it? –Salman Abbas Jul 11 '12 at 1:10 7 According to wiki.bash-hackers.org/scripting/obsolete, it seems to be obsolete in the sense that it is not part of POSIX, but the

And yes, during my research I found some weirdness in the Bash manual page about it, I will ask on the mailing list. Bash Redirect Error To Variable SyntaxDescription FILENAMEreferences a normal, ordinary filename from the filesystem (which can of course be a FIFO, too. That something written on the file descriptor 2 will go where file descriptor 1 goes.


up vote 728 down vote favorite 190 To redirect stdout to a truncated file in Bash, I know to use: cmd > file.txt To redirect stdout in Bash, appending to a Dennis numbers 2.0 Is it possible to check for existence of member template just by identifier? However, your command doesn't work either. Bash Redirect Error Output To /dev/null Plase add this example, http://stackoverflow.com/questions/3141738/duplicating-stdout-to-stderr.

Dec 11 '15 at 14:33 1 Thanks for catching that; you're right, one will clobber the other. Wiki syntax is allowed: Please fill all the letters into the box to prove you're human. Jan Schampera, 2011/02/14 06:31 These are 2 cases. http://onlinetvsoftware.net/bash-redirect/bash-redirect-standard-error-to-file.php Just something to keep in mind.

Any idea why? –Alexandre Holden Daly May 30 '14 at 12:12 1 Note that (by default) this has the side-effect that $? Appending redirected output and error output To append the cumulative redirection of stdout and stderr to a file you simply do >> FILE 2>&1 &>> FILE Transporting stdout and stderr through This means that the STDOUT is redirected first. (When you have > without a stream number, it actually have an implicit 1) And only after STDERR is redirected to "the same The "here document" will do what it's supposed to do, and the * will, too.

Let's start with the outer { } 3>&2 4>&1. --- +-------------+ --- +-------------+ ( 0 ) ---->| /dev/pts/5 | ( 3 ) ---->| /dev/pts/5 | --- +-------------+ --- +-------------+ --- +-------------+ The way to go portable (similar to the appending answers) always was and still is >outfile 2>&1 –TheBonsai May 18 '09 at 4:48 add a comment| 6 Answers 6 active oldest you want to redirect this descriptor, you just use the number: # this executes the cat-command and redirects its error messages (stderr) to the bit bucket cat some_file.txt 2>/dev/null Whenever you Using Map to convert Feet + Inches to Inches in a List of Lists Skeletal formula for carbon with two double bonds How to deal with a really persuasive character?

command < input-file > output-file # Or the equivalent: < input-file command > output-file # Although this is non-standard. bash stdout stderr share|improve this question edited Sep 23 '11 at 10:11 asked Sep 23 '11 at 9:35 sdmythos_gr 1,59621321 2 possible duplicate of Redirect stderr and stdout in a These, and any other open files, can be redirected. the texts "my message" and "Hello again" have been overwritten by the stderr output of the ls commands.

What a helpful and badly needed site! 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". They're evaluated from left to right. bad_command2 2>>$ERRORFILE # Error message appended to $ERRORFILE.