In the commands below, replace &lt;kbd&gt;Ctrl&lt;/kbd&gt; with whatever your escape key is for screen commands.


Try &lt;kbd&gt;Ctrl&lt;/kbd&gt;+&lt;kbd&gt;a&lt;/kbd&gt; &lt;kbd&gt;q&lt;/kbd&gt;, which is the sequence to unblock scrolling.

&lt;kbd&gt;Ctrl&lt;/kbd&gt;+&lt;kbd&gt;a&lt;/kbd&gt; &lt;kbd&gt;s&lt;/kbd&gt; is the sequence that blocks scrolling, which makes screen seem like it freezes.



When **using PuTTY**, you can get an apparently freezed screen if you press &lt;kbd&gt;Ctrl&lt;/kbd&gt;+&lt;kbd&gt;s&lt;/kbd&gt;. 
This sends an [`Xoff` signal][1] blocking the terminal&#39;s output.

The solution is to **press** &lt;kbd&gt;Ctrl&lt;/kbd&gt;+&lt;kbd&gt;q&lt;/kbd&gt; to send the `Xon` signal.


  [1]: http://whatis.techtarget.com/definition/Xon-Xoff-X-on-X-off-or-XON-XOFF

The above works great if that is your issue.

This could also happen if you&#39;re ssh&#39;d into another machine and haven&#39;t been to the window in awhile, then when you go back it&#39;s frozen. To fix this, you can try the following:

1) Create a new window

    Ctrl-a c

2) ssh into the box where you ssh&#39;d into the box in the window that&#39;s frozen.

3) Find the process the ssh is running under:

    ps aux | grep &lt;remote_box_on_frozen_screen&gt;

or

    ps aux | grep &lt;your_user_id&gt;

4) Kill the process

    kill &lt;process_id&gt;




When you do `screen -ls` the first number of the screen name is the process id. So if the output is

    There is a screen on:
	    21605.pts-0.Random-server	(11/12/2017 11:44:15 PM)	(Detached)
    1 Socket in /var/run/screen/S-kg.

Then this will kill it:

    kill 21605

Notice the number for the kill command is the same as in the `screen -ls` output.

If you are using backtick commands in status line - that is, if your `.screenrc` has something like this:

    backtick 1 0 60 /some/script.sh

then you want to be sure that the script is fast: apparently backtick execution blocks all IO to screen.

If you make changes to the config, you&#39;ll need to restart the screen session (as the config applies only to new sessions).

I&#39;m trying to use SED to extract text from a log file. I can do a search-and-replace without too much trouble:

    sed &#39;s/foo/bar/&#39; mylog.txt

However, I want to make the search case-insensitive. From what I&#39;ve googled, it looks like appending `i` to the end of the command should work:

    sed &#39;s/foo/bar/i&#39; mylog.txt

However, this gives me an error message:

    sed: 1: &quot;s/foo/bar/i&quot;: bad flag in substitute command: &#39;i&#39;

What&#39;s going wrong here, and how do I fix it?

Case-insensitive search and replace with sed

I want to convert the following string `&#39;14 2&#39;` into an array of two integers.
How can I do it ?

convert string into array of integers

GNU Screen seems to freeze. Unable to enter user input.  

I was using GNU screen and when I pressed the screen it became unresponsive. I can execute all the GNU screen commands, but can&#39;t enter user input. I don&#39;t want to kill this screen as I have important work and I don&#39;t want to lose it.

The GNU screen is unresponsive, seems blocked

<p>GNU Screen seems to freeze. Unable to enter user input.</p>
<p>I was using GNU screen and when I pressed the screen it became unresponsive. I can execute all the GNU screen commands, but can't enter user input. I don't want to kill this screen as I have important work and I don't want to lose it.</p>


The following grep expression successfully lists all the .exe and .html files in the current directory and sub directories.  

    ls -R |grep -E .*[\.exe]$\|.*[\.html]$  

How do I invert this result to list those that aren&#39;t a .html or .exe instead. (That is, `!=`.)


How to invert a grep expression

I want to find the non-readable files in my directory (eg the files with g-r).  So I tried this:

`find . -perm -g-r`

It shows me all of the files??  So I tried this:

`find . -perm -g+r`

And it showed me only the readable files.  It appears that `-perm -g-r` matches all files.  I&#39;m using CentOS 5.5.  Am I doing something wrong?  It doesn&#39;t look like `-perm -g-r` does anything useful.

Using `find -perm` to find when a permission is not set

    &lt;?php
    $filename = &quot;xx.gif&quot;;
    $handle = fopen($filename, &quot;r&quot;);
    $data = fread($handle, filesize($filename));

    // $data is file data
    $pvars   = array(&#39;image&#39; =&gt; base64_encode($data), &#39;key&#39; =&gt; IMGUR_API_KEY);
    $timeout = 30;
    $curl    = curl_init();

    curl_setopt($curl, CURLOPT_URL, &#39;http://api.imgur.com/2/upload.xml&#39;);
    curl_setopt($curl, CURLOPT_TIMEOUT, $timeout);
    curl_setopt($curl, CURLOPT_POST, 1);
    curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($curl, CURLOPT_POSTFIELDS, $pvars);

    $xml = curl_exec($curl);

    curl_close ($curl);
 
    var_dump($xml);
    ?&gt;

I&#39;m playing with the Imgur API, but it doesn&#39;t seems to work. PHP.net says that `curl_init()` is in PHP5, but my host says it isn&#39;t. How can I make this work?

Fatal error: Call to undefined function curl_init()

It&#39;s frustrating when I do something like `man bindkey` and i get:

&lt;pre&gt;
BUILTIN(1)                BSD General Commands Manual               BUILTIN(1)

NAME
     builtin, !, %, ., :, @, {, }, alias, alloc, bg, bind, bindkey, break, breaksw, builtins, case, cd, chdir, command,
     complete, continue, default, dirs, do, done, echo, echotc, elif, else, end, endif, endsw, esac, eval, exec, exit,
     export, false, fc, fg, filetest, fi, for, foreach, getopts, glob, goto, hash, hashstat, history, hup, if, jobid,
     jobs, kill, limit, local, log, login, logout, ls-F, nice, nohup, notify, onintr, popd, printenv, pushd, pwd, read,
     readonly, rehash, repeat, return, sched, set, setenv, settc, setty, setvar, shift, source, stop, suspend, switch,
     telltc, test, then, time, times, trap, true, type, ulimit, umask, unalias, uncomplete, unhash, unlimit, unset,
     unsetenv, until, wait, where, which, while -- shell built-in commands

SYNOPSIS
     builtin [-options] [args ...]

DESCRIPTION
     Shell builtin commands are commands that can be executed within the running shell&#39;s process.  Note that, in the
&lt;/pre&gt;

Is there an easy way to access the documentation for such commands?


How can I read documentation about built in zsh commands?

I would like to enable all apt repositories in this file

    cat /etc/apt/sources.list
    ## Note, this file is written by cloud-init on first boot of an instance                                                                                                            
    ## modifications made here will not survive a re-bundle.                                                                                                                            
    ## if you wish to make changes you can:                                                                                                                                             
    ## a.) add &#39;apt_preserve_sources_list: true&#39; to /etc/cloud/cloud.cfg                                                                                                                
    ##     or do the same in user-data
    ## b.) add sources in /etc/apt/sources.list.d                                                                                                                                       
    #                                                                                                                                                                                   
                                                                                                                                                                                        
    # See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to                                                                                                           
    # newer versions of the distribution.                                                                                                                                               
    deb http://us-east-1.ec2.archive.ubuntu.com/ubuntu/ maverick main                                                                                                                   
    deb-src http://us-east-1.ec2.archive.ubuntu.com/ubuntu/ maverick main                                                                                                               
                                                                                                                                                                                        
    ## Major bug fix updates produced after the final release of the                                                                                                                    
    ## distribution.                                                                                                                                                                    
    deb http://us-east-1.ec2.archive.ubuntu.com/ubuntu/ maverick-updates main                                                                                                           
    deb-src http://us-east-1.ec2.archive.ubuntu.com/ubuntu/ maverick-updates main                                                                                                       
                                                                                                                                                                                        
    ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu                                                                                                         
    ## team. Also, please note that software in universe WILL NOT receive any                                                                                                           
    ## review or updates from the Ubuntu security team.                                                                                                                                 
    deb http://us-east-1.ec2.archive.ubuntu.com/ubuntu/ maverick universe                                                                                                               
    deb-src http://us-east-1.ec2.archive.ubuntu.com/ubuntu/ maverick universe                                                                                                           
    deb http://us-east-1.ec2.archive.ubuntu.com/ubuntu/ maverick-updates universe
    deb-src http://us-east-1.ec2.archive.ubuntu.com/ubuntu/ maverick-updates universe
    
    ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu 
    ## team, and may not be under a free licence. Please satisfy yourself as to
    ## your rights to use the software. Also, please note that software in 
    ## multiverse WILL NOT receive any review or updates from the Ubuntu
    ## security team.
    # deb http://us-east-1.ec2.archive.ubuntu.com/ubuntu/ maverick multiverse
    # deb-src http://us-east-1.ec2.archive.ubuntu.com/ubuntu/ maverick multiverse
    # deb http://us-east-1.ec2.archive.ubuntu.com/ubuntu/ maverick-updates multiverse
    # deb-src http://us-east-1.ec2.archive.ubuntu.com/ubuntu/ maverick-updates multiverse
    
    ## Uncomment the following two lines to add software from the &#39;backports&#39;
    ## repository.
    ## N.B. software from this repository may not have been tested as
    ## extensively as that contained in the main release, although it includes
    ## newer versions of some applications which may provide useful features.
    ## Also, please note that software in backports WILL NOT receive any review
    ## or updates from the Ubuntu security team.
    # deb http://us-east-1.ec2.archive.ubuntu.com/ubuntu/ maverick-backports main restricted universe multiverse
    # deb-src http://us-east-1.ec2.archive.ubuntu.com/ubuntu/ maverick-backports main restricted universe multiverse
    
    ## Uncomment the following two lines to add software from Canonical&#39;s
    ## &#39;partner&#39; repository.
    ## This software is not part of Ubuntu, but is offered by Canonical and the
    ## respective vendors as a service to Ubuntu users.
    # deb http://archive.canonical.com/ubuntu maverick partner
    # deb-src http://archive.canonical.com/ubuntu maverick partner
    
    deb http://security.ubuntu.com/ubuntu maverick-security main
    deb-src http://security.ubuntu.com/ubuntu maverick-security main
    deb http://security.ubuntu.com/ubuntu maverick-security universe
    deb-src http://security.ubuntu.com/ubuntu maverick-security universe
    # deb http://security.ubuntu.com/ubuntu maverick-security multiverse
    # deb-src http://security.ubuntu.com/ubuntu maverick-security multiverse

With sed this is a simple `sed -i &#39;s/^# deb/deb/&#39; /etc/apt/sources.list` what&#39;s the most elegant (&quot;pythonic&quot;) way to do this?

How to do sed like text replace with python?

I have been using Visual Studio for a while and found that when I open visual studio and open the project all the files that were open last time remain open.

This causes my Visual Studio to freeze or crash on startup.

I am using a lot of plugins in my installation and wonder if there is a way to prevent this from happening.

Visual Studio freezes or hangs on startup

I have a program that frequently uses an external program and reads its outputs.
It works pretty well using your usual process redirect output, but one specific argument for some reason hangs when I try to read it, no error message - no exception, it just &#39;stops&#39; when it reaches that line.
I of course use a centralized function to call and read output from the program, which is this:

    public string ADBShell(string adbInput)
    {
        try
        {
            //Create Empty values
            string result = string.Empty;
            string error = string.Empty;
            string output = string.Empty;
            System.Diagnostics.ProcessStartInfo procStartInfo 
                = new System.Diagnostics.ProcessStartInfo(toolPath + &quot;adb.exe&quot;);

            procStartInfo.Arguments = adbInput;
            procStartInfo.RedirectStandardOutput = true;
            procStartInfo.RedirectStandardError = true;
            procStartInfo.UseShellExecute = false;
            procStartInfo.CreateNoWindow = true;
            procStartInfo.WorkingDirectory = toolPath;
            System.Diagnostics.Process proc = new System.Diagnostics.Process();
            proc.StartInfo = procStartInfo;
            proc.Start();
            // Get the output into a string
            proc.WaitForExit();
            result = proc.StandardOutput.ReadToEnd();
            error = proc.StandardError.ReadToEnd();  //Some ADB outputs use this
            if (result.Length &gt; 1)
            {
                output += result;
            }
            if (error.Length &gt; 1)
            {
                output += error;
            }
            Return output;
        }
        catch (Exception objException)
        {
            throw objException;
        }
    }
The line that hangs is `result = proc.StandardOutput.ReadToEnd();`, but again, not every time, only when sent a specific argument (&quot;start-server&quot;). All other arguments work just fine - it reads the value and returns it.
It&#39;s also strange the way it hangs. It doesn&#39;t freeze or give an error or anything, it just stops processing. As if it was a &#39;return&#39; command, except it doesn&#39;t even return to the calling function, it just stops everything with the interface still up and running.
Anyone experienced this before? Anyone have any idea what I should try? I&#39;m assuming it&#39;s something unexpected within the stream itself, but is there a way I can handle/ignore this so that it reads it anyway?


StandardOutput.ReadToEnd() hangs

Since the ECMA-262 specifications Javascript has gained the *Object.freeze()* method, which allows for objects, whose properties can not be changed, added or removed.

    var obj = {&#39;a&#39;:1, &#39;b:2&#39;};
    Object.freeze(obj);
    Object.isFrozen(obj);       // returns true
    obj.a = 10;                 // new assignment has no affect
    obj.a;                      // returns 1
 
So far so good.

I am wondering, whether freeze() should also work on Arrays.

    var arr = [1, 2];
    Object.freeze(arr);
    Object.isFrozen(arr);      // returns true
    arr[0] = 10;
    arr;                       // returns [10, 2] ... ouch!

Maybe I am wrong, but I was under the impression, that Array inherits from Object.

    typeof obj                 // &quot;object&quot;
    typeof arr                 // &quot;object&quot;


Any ideas, pointers, enlightenments would be highly appreciated.

&#39;Freezing&#39; Arrays in Javascript?

I&#39;m using Windows 7 64 bit. Each time, I&#39;m using plot function, plot windows will shows and draws successfully, but after that it stops responding and must shut down it.

For example :

    x = linspace(0,1,10)
    y = x.^2
    plot(x,y);

Strangely, when plot windows freeze and I must close octave windows, they will be unresponsive too. This will not happen if I don&#39;t use plot function.

I don&#39;t know why. Does it because I&#39;m using 64 bit version? Please tell me how to fix this.

Plot window not responding

A project I&#39;ve been working for 2 months stopped working for no reason because Xcode got stucked on &quot;Indexing&quot;. I can&#39;t Build the project anymore. If I try to build, Xcode freezes and I have to force quit. This happens only with this project.
 
I tried cleaning all derived data but didn&#39;t help.
 
I&#39;m using Xcode 4.5.2.
 
Any ideas?

Xcode stuck on Indexing

Say I want to kill every process containing the word amarok. I can print out the commands I want to execute. But how do I actually make the shell execute them. ie.

    ps aux | grep -ie amarok | awk &#39;{print &quot;kill -9 &quot; $2}&#39;
    Output:
    kill -9 3052
    kill -9 3071
    kill -9 3076
    kill -9 3077
    kill -9 3079
    kill -9 3080
    kill -9 3082
    kill -9 3083
    kill -9 3084
    kill -9 3085
    kill -9 3086
    kill -9 3087
    kill -9 3088
    kill -9 3089
    kill -9 4031

How to kill all processes matching a name?

I want to define a bash alias named `kill3000` to automate the following task:

&lt;!-- language: lang-none --&gt;

    $ lsof -i:3000
    
    COMMAND   PID USER   FD   TYPE  DEVICE SIZE/OFF NODE NAME
    ruby    13402 zero    4u  IPv4 2847851      0t0  TCP *:3000 (LISTEN)
    
    $ kill -9 13402



shell script to kill the process listening on port 3000?

I am trying to kill a process in the command line for a specific port in ubuntu.

If I run this command I get the port:

    sudo lsof -t -i:9001

so...now I want to run:

    sudo kill &#39;sudo lsof -t -i:9001&#39;

I get this error message:

    ERROR: garbage process ID &quot;lsof -t -i:9001&quot;.
    Usage:
      kill pid ...              Send SIGTERM to every process listed.
      kill signal pid ...       Send a signal to every process listed.
      kill -s signal pid ...    Send a signal to every process listed.
      kill -l                   List all signal names.
      kill -L                   List all signal names in a nice table.
      kill -l signal            Convert between signal numbers and names.

I tried `sudo kill &#39;lsof -t -i:9001&#39;` as well


How to kill a process on a port on ubuntu

I understand it&#39;s off topic, I couldn&#39;t find anywhere online and I was thinking maybe programming gurus in the community might know this.  
I usually use 

    kill -9 pid

to kill the job. I always wondered the origin of 9. I looked it up online, and it says

&quot;9 Means KILL signal that is not catchable or ignorable. In other words it would signal process (some running application) to quit immediately&quot; (source: http://wiki.answers.com/Q/What_does_kill_-9_do_in_unix_in_its_entirety)

But, why 9? and what about the other numbers? is there any historical significance or because of the architecture of Unix?


Why number 9 in kill -9 command in unix?

Update: Already fixed, it seems that one of VirtualHosts configurations files was wrong in sites-enabled.

I have Ubuntu 11.10

When I run the command to start apache2:

    sudo /etc/init.d/apache2 start

I get the following error message:

&gt;  Starting web server apache2                                        
&gt; apache2: Could not reliably determine the server&#39;s fully qualified
&gt; domain name, using 127.0.1.1 for ServerName (98)Address already in
&gt; use: make_sock: could not bind to address 0.0.0.0:80 no listening
&gt; sockets available, shutting down Unable to open logs Action &#39;start&#39;
&gt; failed.

I run this command in order to get the process that is using the port 80:

    sudo netstat -ltnp | grep &#39;:80&#39;

Which returns this output:

    tcp6       0      0 :::80                   :::*                    LISTEN      1176/

To know which process is I run this command:

    ps -wlp1176

That returns: 

    F S   UID   PID  PPID  C PRI  NI ADDR SZ WCHAN  TTY          TIME CMD
    5 D    33  1176     1  0  80   0 -     0 exit   ?        00:00:00 apache2

But if I try to kill the process: 

    sudo kill -9 1176

It doesn&#39;t kill it, if I run again the netstat command still appears listening and apache start fails.

Any suggestions?

Starting apache fails (could not bind to address 0.0.0.0:80)

How do I easily copy the GNU Screen scrollback buffer to a file? I.e., a more powerful version of the &#39;hardcopy&#39; command?

In GNU screen, I can use &quot;&lt;kbd&gt;Ctrl&lt;/kbd&gt; + &lt;kbd&gt;A&lt;/kbd&gt; &lt;kbd&gt;Esc&lt;/kbd&gt;&quot; to enter the scrollback
buffer. I could then mark the entire buffer and use &quot;&lt;kbd&gt;Ctrl&lt;/kbd&gt; + &lt;kbd&gt;A&lt;/kbd&gt; &lt;kbd&gt;Ctrl&lt;/kbd&gt; + &lt;kbd&gt;]&lt;/kbd&gt;&quot; to paste it into an [Emacs][1] buffer, thus saving it to a file.

However, this is tedious. Is there a Screen command that&#39;ll simply copy the scrollback buffer to a file, like &#39;hardcopy&#39; does for the visible portion of the screen?

  [1]: https://en.wikipedia.org/wiki/Emacs



Copying the GNU screen scrollback buffer to a file (extended hardcopy)

I `screen -r`&#39;d into a Django server that&#39;s running and I can&#39;t simply &lt;kbd&gt;Ctrl&lt;/kbd&gt; + &lt;kbd&gt;C&lt;/kbd&gt; and `exit` out of it.

Are there any alternative ways to get out of `screen`?

Currently, I manually close the tab on my local PC and `ssh` back in, but that&#39;s becoming tiresome.


How do I get out of &#39;screen&#39; without typing &#39;exit&#39;?

When using screen in linux, how can I tell if I&#39;m in a screen or not?
I could do `exit` and I&#39;ll exit a screen if I was in one, but if I wasn&#39;t, then I&#39;ll end up closing my terminal.

When doing `screen -r`, I could see if I have other screens attached, but how do I know if my current terminal is one of those attached screens?

How can I tell whether I&#39;m in a screen?

I am looking for a terminal multiplexer for Microsoft Windows. I was unable to locate the installers for Microsoft Windows for both tmux and GNU Screen.

Currently I&#39;m using Putty to connect to my Linux machine from from Windows Machine. Can somebody please suggest how to get GNU Screen or tmux working on Windows Platform.

Are there any other good alternatives to above options.

Terminal Multiplexer for Microsoft Windows - Installers for GNU Screen or tmux

I&#39;m starting a number of screens in a bash script, then running django&#39;s `runserver` command in each of them. I&#39;d like to be able to programmatically stop them all as well, which requires me to send `Control+c` to `runserver`.

How can I send these keystrokes from my bash script?

Content Type	Original Author	Original Content on Stackoverflow
Question	sirus	View Question on Stackoverflow
Solution 1 - Linux	逆さま	View Answer on Stackoverflow
Solution 2 - Linux	Daniel Reis	View Answer on Stackoverflow
Solution 3 - Linux	Hazok	View Answer on Stackoverflow
Solution 4 - Linux	Pylinux	View Answer on Stackoverflow
Solution 5 - Linux	Piskvor left the building	View Answer on Stackoverflow

The GNU screen is unresponsive, seems blocked

Linux Problem Overview

Linux Solutions

Solution 1 - Linux

Solution 2 - Linux

Solution 3 - Linux

Solution 4 - Linux

Solution 5 - Linux

convert string into array of integers

Case-insensitive search and replace with sed

Attributions