Home > Bash Script > Bash Script Redirect Standard Error

Bash Script Redirect Standard Error

Contents

Since shells fundamentally use whitespace to delimit fields in general, it is visually much clearer for each redirection to be separated by whitespace, but grouped in chunks that contain no unnecessary If the op is < then there is an implicit 0, if it's > or >>, there is an implicit 1. 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 How does Gandalf get informed of Bilbo's 111st birthday party? Check This Out

To do this, we redirect stdout to the file we want to modify. A. 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 An Example This example comes from this post (ffe4c2e382034ed9) on the comp.unix.shell group: { { cmd1 3>&- | cmd2 2>&3 3>&- } 2>&1 >&4 4>&- | cmd3 3>&- 4>&- } 3>&2

Bash Script Redirect Error Output

Follow him on Twitter. Anyway, many thanks again. )jack( R.W. They will look like: --- +-----------------------+ standard input ( 0 ) ---->| /dev/pts/5 | --- +-----------------------+ --- +-----------------------+ standard output ( 1 ) ---->| file | --- +-----------------------+ --- +-----------------------+ standard

Changing STDOUT after STDERR had been redirected to STDOUT won't change STDERR. it will only redirect the output of that line. # i need something that will work for the rest of the script from here on out. 2>&1 | tee $fileName echo monitor) stderr2standard error output stream (usually also on monitor) The terms "monitor" and "keyboard" refer to the same device, the terminal here. Bash Script Redirect Output To File And Screen Valid redirection targets and sources This syntax is recognized whenever a TARGET or a SOURCE specification (like below in the details descriptions) is used.

To be precise, the following substitutions and expansions are performed in the here-document data: Parameter expansion Command substitution Arithmetic expansion You can avoid that by quoting the tag: cat <<"EOF" This Bash Redirect Standard Error To /dev/null 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 cmd 2>& 1 <<< stuff # Hideously Bad. ARGUMENTS become the arguments to COMMAND.

Here documents <

Bash Redirect Standard Error To /dev/null

Natural construction Video displays in Star Wars What is the sh -c command? Join them; it only takes a minute: Sign up Redirect stderr and stdout in a Bash script up vote 364 down vote favorite 118 I want to redirect both stdout and Bash Script Redirect Error Output no, do not subscribeyes, replies to my commentyes, all comments/replies instantlyhourly digestdaily digestweekly digest Or, you can subscribe without commenting. Bash Script Redirect Stderr To Dev Null Always place redirections together at the very end of a command after all arguments.

I'm very lost with this. http://sovidi.com/bash-script/bash-script-error-log.php I need to have stdout and stderr sent both to stdout and to a file, the file needs to be unique everytime. There are two redirections, the first being: 1> >(some-command) This redirects file descriptor 1 (stdout) to the location >(some-command). op is <, >, >>, >|, or <>: < if the file decriptor in lhs will be read, > if it will be written, >> if data is to be appended Bash Script Redirect Stderr To Variable

Should be: yourcommand &>filename (redirects both stdout and stderr to filename). no outgoing connection via ipv4 Is the following extension of finite state automata studied? Problem? this contact form So what do the redirections do?

cat *.txt | sort | uniq > result-file # Sorts the output of all the .txt files and deletes duplicate lines, # finally saves results to "result-file".But at the start, I would define the log: LOG=/path/to/filename.log then just end each line with "2>&1 | tee $LOG" Sasha, Thanks for the response.

Is the following extension of finite state automata studied? In your first echo, this is the newline after the closing bracket. In the example from comp.unix.shell, you wrote: "Now for the left part of the second pipe…" The illustration for the result confused me because I was assuming the fds where coming Bash Script Redirect All Output To File exec also allow us to manipulate the file descriptors.

Wiki syntax is allowed: Please fill all the letters into the box to prove you're human. Best leave this particular fd alone.

PrevHomeNextHere StringsUpUsing exec
Next Previous LinuxQuestions.org > Forums > Linux Forums > Linux - General redirecting BASH script stdout/stderr from the script itself User Name Remember Me? navigate here If you'd like to contribute content, let us know.

For the wiki quirks: I surrounded your code with ... tags. Because after 2>&1, we have 2 file descriptors pointing to the same file. Jan Schampera, 2012/12/16 14:13 I see those additional line coming from the previous echo: [email protected]:~$ echo -e "$tT" A B C [email protected]:~$ It is the additional newline echo adds itself to The other is to append.

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". Never use the Csh &>foo and >&foo shorthand redirects. Let's see what's going on. I lied, I did not explain 1>&3-, go check the manual Thanks to Stéphane Chazelas from whom I stole both the intro and the example….

It is analogous to a file handle in C.

[3]Using file descriptor 5 might cause problems.