ubuntu how to locate what you want (the path, the file etc.)

part 1  find the path

the first 5 ways are excuted with terminals, the 6-th is gui, the 7-th varies.

Based on the pipiline tech, the 'grep' can be combined with all the following ways.

 

1 dpkg show the installed packages (only packages by the synaptic manager usually .deb type)

 first, we should know the organized structure of linux distributions. In Linux distributions, a “package” refers to a compressed file archive containing all of the files that come with a particular application. The files are usually stored in the package according to their relative installation paths on your system. Most packages also contain installation instructions for the OS, as well as a list of any other packages that are dependencies (prerequisites required for installation.

Common types of Linux packages include .deb, .rpm, and .tgz. Since Linux packages do not usually contain the dependencies necessary to install them, many Linux distributions use package managers that automatically read dependencies files and download the packages needed before proceeding with the installation. Some examples of package managers are APT, YUM, and Pacman.

ex 

dpkg -s dpkg | grep Status
Status: install ok installed

more detail:http://www.cyberciti.biz/howto/question/linux/dpkg-cheat-sheet.php

2 whereis: locate the binary, source, and manual page files for a command

ex whereis *python*

3 which :locate a command; returns the pathnames of the files (or links) which would be executed in the current environment,

4 locate 

Locate is used more like a keyword-based search function.

ex locate java ;  the returned result is large

5 find : search for files in a directory hierarchy

ex :  find / -xdev -type f -a -name 'java*'

compared with 4, this way has connection with the directory 

6 gui such as

 6.1 places->search for files->input the keywords and set the folder

6.2 the synaptic manager search

7 other tools such as 

xfce4-appfinder

Beagle

 

part 2 find special text string with some known information

1 grep : print lines matching a pattern

http://vim.wikia.com/wiki/Find_in_files_within_Vim

2 ctags+cscope

3 global

etc....

 

here thanks to Mr. Wu