The canonical way to query the */etc/passwd* file for this information is with `getent`. You can parse `getent` output with standard tools such as `cut` to extract the user&#39;s login shell. For example:

    $ getent passwd $LOGNAME | cut -d: -f7
    /bin/bash

The command is `finger`.

    [ken@hero ~]$ finger ken
    Login: ken            			Name: Kenneth Berland
    Directory: /home/ken                	Shell: /bin/tcsh
    On since Fri Jun 15 16:11 (PDT) on pts/0 from 70.35.47.130
       1 hour 59 minutes idle
    On since Fri Jun 15 18:17 (PDT) on pts/2 from 70.35.47.130
    New mail received Fri Jun 15 18:16 2012 (PDT)
         Unread since Fri Jun 15 17:05 2012 (PDT)
    No Plan.



The login shell is defined in `/etc/passwd`. So you can do:

    grep username /etc/passwd


I think what you are looking for is this:

    #!/bin/bash
    grep &quot;^$1&quot; /etc/passwd | cut -d &#39;:&#39; -f 7

Save that as `get-shell` somewhere in your path (probably ~/bin) and then call it like:

    get-shell userfoo

`SHELL` variable is used to represent user&#39;s current shell

    echo $SHELL



I have an URI image file, and I want to reduce its size to upload it. Initial image file size depends from mobile to mobile (can be 2MB as can be 500KB), but I want final size to be about 200KB, so that I can upload it.&lt;br&gt;
From what I read, I have (at least) 2 choices:

- Using *BitmapFactory.Options.inSampleSize*, to subsample original image and get a smaller image;&lt;br&gt;
- Using *Bitmap.compress* to compress the image specifying compression quality.&lt;br&gt;

What&#39;s the best choice?
****
I was thinking to initially resize image width/height until width or height is above 1000px (something like 1024x768 or others), then compress image with decreasing quality until file size is above 200KB. Here&#39;s an example:&lt;br&gt;

    int MAX_IMAGE_SIZE = 200 * 1024; // max final file size
    Bitmap bmpPic = BitmapFactory.decodeFile(fileUri.getPath());
    if ((bmpPic.getWidth() &gt;= 1024) &amp;&amp; (bmpPic.getHeight() &gt;= 1024)) {
        BitmapFactory.Options bmpOptions = new BitmapFactory.Options();
        bmpOptions.inSampleSize = 1;
        while ((bmpPic.getWidth() &gt;= 1024) &amp;&amp; (bmpPic.getHeight() &gt;= 1024)) {
            bmpOptions.inSampleSize++;
            bmpPic = BitmapFactory.decodeFile(fileUri.getPath(), bmpOptions);
        }
        Log.d(TAG, &quot;Resize: &quot; + bmpOptions.inSampleSize);
    }
    int compressQuality = 104; // quality decreasing by 5 every loop. (start from 99)
    int streamLength = MAX_IMAGE_SIZE;
    while (streamLength &gt;= MAX_IMAGE_SIZE) {
        ByteArrayOutputStream bmpStream = new ByteArrayOutputStream();
        compressQuality -= 5;
        Log.d(TAG, &quot;Quality: &quot; + compressQuality);
        bmpPic.compress(Bitmap.CompressFormat.JPEG, compressQuality, bmpStream);
        byte[] bmpPicByteArray = bmpStream.toByteArray();
        streamLength = bmpPicByteArray.length;
        Log.d(TAG, &quot;Size: &quot; + streamLength);
    }
    try {
        FileOutputStream bmpFile = new FileOutputStream(finalPath);
        bmpPic.compress(Bitmap.CompressFormat.JPEG, compressQuality, bmpFile);
        bmpFile.flush();
        bmpFile.close();
    } catch (Exception e) {
        Log.e(TAG, &quot;Error on saving file&quot;);
    }

Is there a better way to do it? Should I try to keep using all 2 methods or only one? Thanks

Android - Reduce image file size

What is the difference between C++11 `std::this_thread::yield()` and `std::this_thread::sleep_for()`? How to decide when to use which one?

std::this_thread::yield() vs std::this_thread::sleep_for()

What is the *nix command to view a user&#39;s default login shell?

I can change the default login shell with `chsh`, but I don&#39;t know how to get what is the user&#39;s default shell.

Pseudocode

    $ get-shell
    /usr/bin/zsh


What is the *nix command to view a user&#39;s default login shell

What is the *nix command to view a user's default login shell?
I can change the default login shell with <code>chsh</code>, but I don't know how to get what is the user's default shell.
Pseudocode
<pre><code class="hljs language-arduino">$ get-shell
/usr/bin/zsh
</code></pre>

After reading the [Bash man pages][1] and with respect to [this post][2], I am still having trouble understanding what exactly the `eval` command does and which would be its typical uses.

For example, if we do:

```lang-none
$ set -- one two three  # Sets $1 $2 $3
$ echo $1
one

$ n=1
$ echo ${$n}       ## First attempt to echo $1 using brackets fails
bash: ${$n}: bad substitution

$ echo $($n)       ## Second attempt to echo $1 using parentheses fails
bash: 1: command not found

$ eval echo \${$n} ## Third attempt to echo $1 using &#39;eval&#39; succeeds
one
```

What exactly is happening here and how do the dollar sign and the backslash tie into the problem?

  [1]: https://linux.die.net/man/1/bash
  [2]: http://www.unix.com/shell-programming-scripting/66063-eval-shell-scripting.html






The &#39;eval&#39; command in Bash and its typical uses

I am trying to give sudo access to one of my users. What should I type in my terminal?

How to give a Linux user sudo access?

I use the following bash script to copy only files of certain extension(in this case *.sh), however it still copies over all the files.  what&#39;s wrong?
&lt;pre&gt;
from=$1
to=$2

rsync -zarv  --include=&quot;*.sh&quot; $from $to
&lt;/pre&gt;


rsync copy over only certain types of files using include option

I am porting an application from Solaris to Linux

The object files which are linked do not have a main() defined. But compilation and linking is done properly in Solaris and executable is generated. In Linux I get this error 

        /usr/lib/gcc/x86_64-redhat-linux/4.1.2/../../../../lib64/crt1.o: In function `_start&#39;:
    (.text+0x20): undefined reference to `main&#39; 

My problem is, I cannot include new .c/.o files since its a huge application and has been running for years. How can I get rid of this error?

Code extractes of makefile:

    RPCAPPN = api
    LINK = cc 

        $(RPCAPPN)_server: $(RPCAPIOBJ)
                $(LINK) -g $(RPCAPIOBJ) -o $(RPCAPPN)_server $(IDALIBS) $(LIBS) $(ORALIBS) $(COMMONLIB) $(LIBAPI) $(CCLIB) $(THREADLIB) $(DBSERVERLIB) $(ENCLIB)



crt1.o: In function `_start&#39;: - undefined reference to `main&#39; in Linux

I want to get the details of the last run cron job. If the job is interrupted due to some internal problems, I want to re-run the cron job. 

Note: I don&#39;t have superuser privilege.

Details of last ran cron job in Unix-like systems?

Instead of having to type `tmux` every time, **how could I have `tmux` always be used for new session windows**?

So if I have no terminal windows open and then I open one, how can that first session be in `tmux`?

Seems like a `.bashrc` sort of thing perhaps?

How can I make TMUX be active whenever I start a new shell session?

How can I convert tabs to spaces in every file of a directory (possibly recursively)?

Also, is there a way of setting the number of spaces per tab?

How can I convert tabs to spaces in every file of a directory?

Bash is quite verbose when running jobs in the background:

    $ echo toto&amp;
    toto
    [1] 15922
    [1]+  Done                    echo toto

Since I&#39;m trying to run jobs in parallel and use the output, I&#39;d like to find a way to silence bash. Is there a way to remove this superfluous output?

Is there a way to make bash job control quiet?

I have a string in the format &quot;yyyymmdd&quot;. It is a string in bash and I want to get it converted into a date so that all other date functions can be used on it.

&quot;20121212&quot; string into &quot;20121212&quot; date with format &quot;%Y%m%d&quot;.



Convert string to date in bash

I&#39;m trying to work out a command which deletes sql files older than 15 days.

The find part is working but not the rm.

    rm -f | find -L /usr/www2/bar/htdocs/foo/rsync/httpdocs/db_backups -type f  $ -name &#39;*.sql&#39; $ -mtime +15

It kicks out a list of exactly the files I want deleted but is not deleting them.  The paths are correct.  

    usage: rm [-f | -i] [-dIPRrvW] file ...
           unlink file
    /usr/www2/bar/htdocs/foo/rsync/httpdocs/db_backups/20120601.backup.sql
    ...
    /usr/www2/bar/htdocs/foo/rsync/httpdocs/db_backups/20120610.backup.sql

What am I doing wrong?

Command line: piping find results to rm

I have `d1=&quot;11&quot;` and `d2=&quot;07&quot;`. I want to convert `d1` and `d2` to integers and perform `d1-d2`. How do I do this in UNIX?

`d1 - d2` currently returns `&quot;11-07&quot;` as result for me.

Content Type	Original Author	Original Content on Stackoverflow
Question	k107	View Question on Stackoverflow
Solution 1 - Linux	Todd A. Jacobs	View Answer on Stackoverflow
Solution 2 - Linux	user1460011	View Answer on Stackoverflow
Solution 3 - Linux	timos	View Answer on Stackoverflow
Solution 4 - Linux	Lucas	View Answer on Stackoverflow
Solution 5 - Linux	nilsocket	View Answer on Stackoverflow

What is the *nix command to view a user's default login shell

Linux Problem Overview

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std::this_thread::yield() vs std::this_thread::sleep_for()

Android - Reduce image file size

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