Debian Wheezy: resize/scale images from command line.

First of all you need to have installed imagemagick.
If no, install it from terminal as root so:

apt-get install imagemagick

Now you are ready to convert input.jpg file into output.jpg file for a 1000 pixels of width and 500 pixels of height....

convert -scale 1000x500 input.jpg output.jpg 

The scale method, in this case, depends of the height and the weight of your image.
So if your image is 2 pixels of width and 1 pixels of height the perform will gone exactly.

Differently the perform will be approximated.

If you want to force the scale performing to make a image of gived dimensions...

convert -scale 1000x500! input.jpg output.jpg

If you have multiple files to convert use this:

for i in $( ls *.JPG); do convert -resize 1300x500 $i $i; done
 
Bye.

Debian Wheezy: mounting windows shared folder

First of all install cifs-utils smbclient packets, to browse and mount net folders..
So from command line:
apt-get install smbclient cifs-utils

Then you need to create a local folder to map remote folder
mkdir /home/username/example_folder

Then you can mount the remote folder by executing this:
mount -t cifs -o username=remote_pc_username //remote_pc_ip_address/remote_folder_shared_name /home/username/example_folder

Where:
remote_pc_username is the username of remote pc
remote_pc_ip_address is the remote ip address
remote_folder_shared_name is the name that the shared folder has into the local net.

Example 2:
mount -t cifs -o username=pippo //192.168.1.2/shared /home/pluto/example_folder


Terminal will prompts to you the password request....
Give it and then you will have correctly mapped your remote folder into your local example_folder


Bye..

Freepops under Debian Wheezy 7.0.1

Freepops is a free for use software that give you the capability to open a gateway to remote resources with pop3 protocol. 

From terminal, as root, install freepops

apt-get install freepops


After, you make under /bin two files.......
The file  freepopsd_start.sh contains:
#!/bin/bash
freepopsd &

And the file  freepopsd_stop.sh contains:
#!/bin/bash
freepopsd -k &



Now from command line of your current user you can give those commands to startup or shutdown the "tunnel".... 
Often before you run you email client...

Bye.... 

Linux: search a file

Simply and fast..... if you are searching a file that you have absolutely forget the path, you can run this by terminal:

locate yourfilename.txt

Important: locate use an indexed system of file research.
For mantains this system update you have to execute periodically this command from terminal....

updatedb

Bye..

Debian Wheezy 7.1: quick samba setup

From command line

apt-get install samba smbclient

during installation, it performs default configuration

after....

adduser guest --home=/home/public --shell=/bin/false --disabled-password

to create a guest user to use only as samba default user...

chmod -R 0700 /home/public
chown -R guest.guest /home/public

These commands configure the sharing in way of every user can create a content(file or folder)

into the shared folder.

No one may edit the content created by someone others.... 

If you want some of differently, change the permission mask.....

Now edit /etc/samba/smb.conf

adding after the row obey pam restrictions = yes

insert these rows: 

guest account = guest
invalid users = root

and in the *Authentication* section,  this row.....: 

security = share

In the sharing section add:

# SHARED DIR
[shared]
   comment = shared
   read only = no
   path = /home/public
   guest ok = yes
   guest only = yes
   create mask = 0600
   directory mask = 0700
 

Fine...... restart samba:

 /etc/init.d/samba restart

and all is done.....

Bye...

Linux: how to check ram usage

This is quickly command to check ram available on you system...
From terminal execute:

free -k

This command extract info from the /proc/meminfo file.
So if you open this file you see a complete set of information about your system memory.

Bye..

Linux: symbolic link(shortcut) from terminal

From terminal exceute:

ln -s /full_path_whereyouwanttopoint /full_path_alias_command_name

Bye...