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Bash Redirect Error Output To Variable


If you want to capture the output, you use command substitution: 1 output=$(command) # stdout only; stderr remains uncaptured 2 output=$(command 2>&1) # both stdout and stderr will be captured 3 Is the standard Canon 18-55 lens the same as 5 years ago? 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 When taking passengers, what should I do to prepare them? this contact form

What are the canonical white spaces? exec 3<> File # Open "File" and assign fd 3 to it. What if you want the exit status of one command from a pipeline? It sets up a couple of extra file descriptors to manage the redirections needed in order to do this. #!/bin/bash exec 3>&1 4>&2 #set up extra file descriptors error=$( { ./useless.sh

Bash Redirect Output To Variable Filename

What does the "Phi" sign stand for in musical notation? Done. The assignment to output has no effect on command's exit status, which is still in $?. What you cannot do is capture stdout in one variable, and stderr in another, using only FD redirections.

I still want the standard output, and I want it to do other things, go other places. –psycotica0 Jun 7 '09 at 16:50 add a comment| up vote 2 down vote Password Protected Wifi, page without HTTPS - why the data is send in clear text? Edit: This really does work. Bash Capture Stderr To Variable 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

Skipping directly to level 4 How to make different social classes look quite different? Bash Redirect Command Output To Variable I would like to do something like this inside of my bash script sh -c path/myExcecutable-bin 2>&1 =MYVARIABLE How do you send stderror output to a variable ? Why are some programming languages Turing complete but lack some abilities of other languages? bash scripting string share|improve this question asked May 29 '14 at 7:25 Miguel Roque 1172412 I tried running this command: var=$(/sbin/modprobe -n -v hfsplush) And then displaying it: $var

Then: { bout=$(banana); } 2>&1; declare -p bout >&2 will do as above, but will also display on the terminal (via stderr) the content of bout with the declare builtin: this Bash Capture Stderr To File It is sometimes useful to assign one of these additional file descriptors to stdin, stdout, or stderr as a temporary duplicate link. [3] This simplifies restoration What the script writes to FD 1 (normally stdout) will be written to stderr because of the first and third redirections. Why?

Bash Redirect Command Output To Variable

So, basically, I want to do ./useless.sh 2> $ERROR | ... Symbolic comparison of recursive functions Verbs of buttons on websites Finding a file starting with '-' dash How to indicate you are going straight? Bash Redirect Output To Variable Filename How to pluralize "State of the Union" without an additional noun? Bash Redirect Error Output To File After checking this, I know I won't make this mistake again. –Stephan Oct 11 '12 at 14:34 @Stephan cheers, this has also been discussed here. :) –Shadow Wizard Oct

At this point, you'll have on your terminal screen: declare -- bout="banana to stdout" declare -- berr="banana to stderr" with the line declare -- bout="banana to stdout" being displayed via stderr. http://waspsoft.com/bash-redirect/bash-redirect-error-output.html Activate Hearthstone season chest cards? See my changes. –Tim Pote Jun 18 '12 at 17:08 add a comment| Not the answer you're looking for? Realism of a setting with several sapient anthropomorphic animal species My home country claims I am a dual national of another country, the country in question does not. Bash Redirect Error Output To /dev/null

  1. no outgoing connection via ipv4 Why don't most major game engines use gifs for animated textures?
  2. Natural construction Is the empty set homeomorphic to itself?
  3. I am not certain I understand the issue well enough at this point to determine how to resolve it yet. –John Mark Mitchell Apr 13 at 20:36 @gniourf_gniourf My
  4. The redirection applies only to the program itself.
  5. local output="$( { local stdout stdout="$($*)" local exitcode=$?
  6. This is why pipes work.
  7. And if you want the exit code of your cmd (here a modification in the case of if the cmd stdout nothing) 1 cmd() { curl -s -v http://www.google.fr; } 2
  8. In the subprocess (process 2): Execute the file ./segfault, i.e.
  9. I haven't quite gotten it to work yet.
  10. bash stderr share|improve this question edited Jun 18 '12 at 16:57 Tim Pote 13.4k23344 asked Jun 18 '12 at 16:55 stackoverflow 4,0212380143 marked as duplicate by tripleeebash Users with the bash

Can a creature benefit from differently typed speed bonuses all named fast movement? BTW, I use this in my dotfiles share|improve this answer answered Feb 13 '15 at 6:22 wener 1364 add a comment| up vote 2 down vote To append to a file 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 # navigate here up vote 5 down vote favorite 1 I was tasked to create an automated server hardening script and one thing that they need is a report of all the output of

UNIX is a registered trademark of The Open Group. Bash Capture Stderr And Stdout To Variable stderr is redirected to stdout, which is then redirected to a file. Harris Jun 18 '13 at 17:58 it worked fine in bash 4.2, and 4.1, i even tried the shopts: compat32, compat31, and it worked there fine too, maybe it

ERROR=$( { ./useless.sh | sed s/Output/Useless/ > outfile; } 2>&1 ) Note that the semi-colon is needed (in classic shells - Bourne, Korn - for sure; probably in Bash too).

This helps me implement a dry_run function that can reliably choose between echoing its arguments and running them, regardless of whether the command being dry-ran is being piped to some other Thanks. –psycotica0 Jun 11 '09 at 21:20 3 If you don't need the standard output, you can redirect it to /dev/null instead of outfile (If you're like me, you found Will the medium be able to last 100 years? Bash Redirect Stdout And Stderr To Different Variables Browse other questions tagged bash scripting string or ask your own question.

Since the list is executed in a subshell, variable assignments do not remain in effect after the subshell completes.{} { list; } Placing a list of commands between curly braces causes ret=`{ ./segfault; } 2>&1` The form ret=`eval ./segfault 2>&1` applies the redirection to the whole evaluation of the eval command, so in principle it should work, and it does in fact Activate Hearthstone season chest cards? his comment is here I've tested it: #!/bin/bash BLAH=$(( ( echo out >&1 echo err >&2 ) 1>log ) 2>&1) echo "BLAH=$BLAH" will print BLAH=err and the file log contains out.

How to indicate you are going straight? Then: berr=$({ bout=$(banana); } 2>&1; declare -p bout >&2); declare -p berr will assign to berr the stderr of banana and display the content of berr with declare. Limit involving exponentials and arctangent without L'Hôpital Were slings used for throwing hand grenades? I want to store the error message inside a string and append it in a text file.

I could redirect stderr into stdout if I wanted to capture both. share|improve this answer answered Jan 17 at 23:53 Gilles 369k666681119 add a comment| Your Answer draft saved draft discarded Sign up or log in Sign up using Google Sign up asked 3 years ago viewed 19353 times active 5 months ago Get the weekly newsletter! What could cause the throttle to stick in my Ford Ranger?

As written, it would capture errors from sed too. (Formally untested code - use at own risk.) share|improve this answer edited May 31 '12 at 1:46 answered Jun 7 '09 at However, in the case of ret=`{ ./segfault; } 2>&1`, process 2 has its standard error redirected to file descriptor 1, but process 1 doesn't. Can you think of a solution for this? Subtraction with a negative result How rich can one single time travelling person actually become?

Process substitution has bought me the ability to work with a data stream which is no longer in STDERR, unfortunately I don't seem to be able to manipulate it the way bash scripting redirect stdout stderr share|improve this question edited Jun 28 '10 at 6:15 msw 31.9k54689 asked Jun 28 '10 at 6:06 thornate 1,08472034 marked as duplicate by tripleeebash Users with It would be more efficient for process 1 to recycle itself. There are three consecutive attempts.

create a shell subprocess. First, keep in mind that 1>&3- is equivalent to 1>&33>&-. On THE other hand or on another hand? In addition to the creation of a subshell, there is a subtle difference between these two constructs due to historical reasons.

I'm hoping there's another way. This way what the script writes to FD 2 (normally stderr) will be written to stdout because of the second redirection. Religious supervisor wants to thank god in the acknowledgements How to make different social classes look quite different? share|improve this answer edited Oct 11 '12 at 9:14 Stephan 20.6k2599162 answered Jul 25 '12 at 23:35 tfga 214 1 @Stephan what's the point in your edit?? –Shadow Wizard Oct