linux command solution for problems

1.find the install path of some software
    like python:   

dpkg -L python

    or the start path:

which python
/usr/bin/python

    or want to display some system environment variable

warrior@warrior:~$ echo $PATH
/usr/local/sbin:/usr/local/bin:

2.manage .deb package in ubuntu 
    install a source package :

warrior@warrior:~/Downloads$ sudo dpkg -i xpdf_3.03-16+experimental2_amd64.deb
[sudo] password for warrior:
Selecting previously unselected package xpdf.
(Reading database ... 285114 files and directories currently installed.)
Preparing to unpack xpdf_3.03-16+experimental2_amd64.deb ...
Unpacking xpdf (3.03-16+experimental2) ...
Setting up xpdf (3.03-16+experimental2) ...
Processing triggers for mime-support (3.54ubuntu1.1) ...
Processing triggers for man-db (2.6.7.1-1ubuntu1) ...
Processing triggers for gnome-menus (3.10.1-0ubuntu2) ...
Processing triggers for desktop-file-utils (0.22-1ubuntu1) ...
Processing triggers for bamfdaemon (0.5.1+14.04.20140409-0ubuntu1) ...
Rebuilding /usr/share/applications/bamf-2.index...

If dpkg reports an error due to dependency problems, you can run sudo apt-get install -f to download the missing dependencies and configure everything.
    
    To remove a Debian (Ubuntu) package (.deb):

sudo dpkg -r packagename

    To Reconfigure/Repair an installed Debian (Ubuntu) package (.deb):

sudo dpkg-reconfigure packagename

for detial U can visit:  

3.some package command 
    <1> zip
    我们可以使用下列的命令压缩一个目录：    

zip -r archive_name.zip directory_to_compress

    下面是如果解压一个zip文档：

unzip archive_name.zip

    <2> tar
    打包一个目录：

tar -cvf archive_name.tar directory_to_compress

     解包：  

tar -xvf archive_name.tar.gz

    也可以用这个命令来设置解包的路径：    

tar -xvf archive_name.tar -C /tmp/extract_here/

    <3> tar.gz
    压缩一个目录：

tar -zcvf archive_name.tar.gz directory_to_compress

    解压缩：

tar -zxvf archive_name.tar.gz

    <4> tar.bz2

    使用tar.bz2进行压缩。 

tar -jcvf archive_name.tar.bz2 directory_to_compress

    解包命令：    

tar -jxvf archive_name.tar.bz2