The only cross platform method I found which works in both interactive and non-interactive shells is:

    command | tee &gt;(cat 1&gt;&amp;2)

The argument to tee is a file or file handle. Using [process substitution][1] we send the output to a process. In the process =cat=, we redirect stdout to stderr. The shell (bash/ksh) is responsible for setting up the 1 and 2 file descriptors. 


  [1]: http://en.wikipedia.org/wiki/Process_substitution

    ./script.sh | tee /dev/fd/2

Note that this is dependant on OS support, not any built-in power in tee, so isn&#39;t universal (but will work on MacOS, Linux, Solaris, FreeBSD, probably others).

    ./script.sh 2&gt;&amp;1 &gt;/dev/null | tee stderr.out

That opens STDERR to STDOUT, and then disposes of STDOUT.

I want to display an alert box showing a message with PHP.

Here is my PHP code:

    &lt;?php  
      header(&quot;Location:form.php&quot;);
        
      echo &#39;&lt;script language=&quot;javascript&quot;&gt;&#39;;
      echo &#39;alert(message successfully sent)&#39;;  //not showing an alert box.
      echo &#39;&lt;/script&gt;&#39;;
      exit;
    ?&gt;

But it is not working.

How to show an alert box in PHP?

I am using Jake&#39;s [ViewPageIndicator][1] and want to display Images like a swipe gallery.
Any refernce link where i can get started. I have implemented the basic viewpager and now want to implement image viewpaper as below

![enter image description here][2]



Is it possible to to achieve using [ViewPageIndicator][1] ?

  [1]: http://viewpagerindicator.com/
  [2]: http://i.stack.imgur.com/gTiUc.png

Android Viewpager as Image Slide Gallery

I want to split `stdout` so that it is printed both to `stdout` and `stderr`.  This sounds like a job for `tee` but the syntax is evading me -

    ./script.sh | tee stderr

Of course, how should `stderr` actually be referred to here?

How to tee to stderr?

I want to split <code>stdout</code> so that it is printed both to <code>stdout</code> and <code>stderr</code>. This sounds like a job for <code>tee</code> but the syntax is evading me -
<pre><code class="hljs language-bash">./script.sh | tee stderr
</code></pre>
Of course, how should <code>stderr</code> actually be referred to here?

I know this syntax

    var=`myscript.sh`
or

    var=$(myscript.sh)

Will capture the result (`stdout`) of `myscript.sh` into `var`. I could redirect `stderr` into `stdout` if I wanted to capture both.  How to save each of them to separate variables?

My use case here is if the return code is nonzero I want to echo `stderr` and suppress otherwise.  There may be other ways to do this but this approach seems it will work, if it&#39;s actually possible.

Capture both stdout and stderr in Bash

If `inner.sh` is

    #...
    echo first
    echo second
    echo third

And `outer.sh` is

    var=`./inner.sh`
    # only wants to use &quot;first&quot;...  

How can `var` be split by whitespace?

    

Capture multiline output as array in bash

After following the instructions on [Doug Hellman&#39;s `virtualenvwrapper` post](https://doughellmann.com/posts/virtualenvwrapper/), I still could not fire up a test environment.

    [mpenning@tsunami ~]$ mkvirtualenv test
    -bash: mkvirtualenv: command not found
    [mpenning@tsunami ~]$

It should be noted that I&#39;m using `WORKON_HOME` that is not in my `$HOME`.  I tried looking for `/usr/local/bin/virtualenvwrapper.sh` as shown in the [`virtualenvwrapper` installation docs](http://virtualenvwrapper.readthedocs.org/en/latest/install.html), but it does not exist.

I&#39;m running CentOS 6 and python 2.6.6, if this matters.

&lt;hr&gt;

    # File: ~/.bash_profile
    # ...
    
    export WORKON_HOME=&quot;/opt/virtual_env/&quot;
    source &quot;/opt/virtual_env/bin/virtualenvwrapper_bashrc&quot;
   



bash: mkvirtualenv: command not found

I have directories named as:

	2012-12-12
	2012-10-12
	2012-08-08
	
How would I delete the directories that are older than 10 days with a bash shell script?

Shell script to delete directories older than n days

In bash script, what does `#!/bin/bash` at the 1st line mean ?


**UPDATE**: Is there a difference between `#!/bin/bash` and `#!/bin/sh` ?

Bash Script : what does #!/bin/bash mean?

It seems that newer versions of bash have the `&amp;&gt;` operator, which (if I understand correctly), redirects both stdout and stderr to a file (`&amp;&gt;&gt;` appends to the file instead, as Adrian clarified). 

What&#39;s the simplest way to achieve the same thing, but instead piping to another command?

For example, in this line:

    cmd-doesnt-respect-difference-between-stdout-and-stderr | grep -i SomeError

I&#39;d like the grep to match on content both in stdout and stderr (effectively, have them combined into one stream).

*Note*: this question is asking about piping, *not* redirecting - so it is not a duplicate of the question it&#39;s currently marked as a duplicate of.

Piping both stdout and stderr in bash?

I am trying to redirect all output from a command line programme to a file.  I am using Bash.  Some of the output is directed to a the file, but some still appears in the terminal and is not stored to the file.  

Similar symptoms are described here:

https://stackoverflow.com/questions/6674327/redirect-all-output-to-file

However I have tried the proposed solution (capture stderr) without success:

    &lt;cmd&gt; &lt;args&gt; &gt; stdout.txt 2&gt; stderr.txt

The file stderr.txt is created but is empty.

A possible clue is that the command-line programme is a client communicating with a server on the same machine.  It may be that some of the output is coming from the **server**.  

Is there a way to capture all the output from the terminal, irrespective of its origin?

**EDIT:**

I&#39;ve confirmed that the missing output is generated by the server.  Running the command in a separate terminal causes some output in both terminals, I can pipe all the output from the command terminal to a file.  This raises issues about how to capture the server output, but that&#39;s a different question.


Redirect all output to file using Bash on Linux?

I want to get the `stdout` in a variable after running the `os.system` call.

Lets take this line as an example: 

    batcmd=&quot;dir&quot;
    result = os.system(batcmd)

`result` will contain the error code (`stderr` `0` under Windows or `1` under some linux for the above example).

How can I get the `stdout` for the above command without using redirection in the executed command?      


Python: How to get stdout after running os.system?

I&#39;m learning the language from Programming Ruby 1.9, and they toss STDERR.puts into a block of code early in the book without explaining why they&#39;re using it or how it&#39;s different from puts.

I&#39;ve googled and wikied the term, but all I can gather from my research is that it&#39;s involved in diagnostics. Nowhere in the code provided by Programming Ruby does there seem to be a link to error exception handling. 

Here&#39;s the code. 

    require_relative &#39;csv_reader&#39;
    reader = CsvReader.new
    ARGV.each do |csv_file_name|
      STDERR.puts &quot;Processing #{csv_file_name}&quot;
      reader.read_in_csv_data(csv_file_name)
    end

I did manage to read somewhere that STDERR.puts is used for error handling out of convention, but I guess I&#39;m asking if it acts any differently than puts.


How is STDERR.puts different from puts in Ruby?

I made a python script which communicates with a web server using an infinite loop.
I want to log every communication data to a file and also monitor them from terminal at same time. so I used tee command like this.

    python client.py | tee logfile

however, I got nothing from terminal nor logfile.
the python script is working fine.
what is happening here?
am I missing something?

some advice would be appreciated.
thank you in advance.

Content Type	Original Author	Original Content on Stackoverflow
Question	djechlin	View Question on Stackoverflow
Solution 1 - Bash	brianegge	View Answer on Stackoverflow
Solution 2 - Bash	Nicholas Wilson	View Answer on Stackoverflow
Solution 3 - Bash	David W.	View Answer on Stackoverflow

How to tee to stderr?

Bash Problem Overview

Bash Solutions

Solution 1 - Bash

Solution 2 - Bash

Solution 3 - Bash

Android Viewpager as Image Slide Gallery

How to show an alert box in PHP?

Attributions