session3.md fixes

session3.md

@@ -2,7 +2,7 @@
 
 Refer [AptCLI](https://wiki.debian.org/AptCLI)
 
-apt and aptitude are two popular command line package management tools for Debian. The session discussed usage of apt.
+`apt` and `aptitude` are two popular command line package management tools for Debian. The session discussed usage of `apt`.
 
 ## Basic Commands
     * `apt install <package>` installs package
@@ -18,19 +18,23 @@ apt and aptitude are two popular command line package management tools for Debia
 ### Serch package a file belongs to
 
 Refer [apt-file](https://wiki.debian.org/apt-file)
+
 `apt-file search <filename>` can be used to find the package in which a file is included.
+
     jyothisjagan@jyothisjagan:~$ apt-file search pq-fe.h
     libpq-dev: /usr/include/postgresql/libpq-fe.h
 
 `dpkg -S <filename>` is similar, but you need to have the package installed.
 
 #### Other Options
+
   * https://packages.debian.org for the search on packages.
   * https://tracker.debian.org will tell you details about a package (versions, version control, various automated test results and other details relevant to a package maintainer)
 
 
 ## dpkg
 `dpkg -l <pattern>` lists packages matching given pattern. 'dpkg -l' lists all packages installled in the system.
+
     jyothisjagan@jyothisjagan:~$ dpkg -l
     Desired=Unknown/Install/Remove/Purge/Hold
     | Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
@@ -47,7 +51,8 @@ Refer [apt-file](https://wiki.debian.org/apt-file)
     ...
 
 
-`dpkg -L <package>` lista files installed to the system from a package
+`dpkg -L <package>` lists files installed to the system from a package
+
     jyothisjagan@jyothisjagan:~$ dpkg -L micro 
     /.
     /usr
@@ -64,6 +69,7 @@ Refer [apt-file](https://wiki.debian.org/apt-file)
     /usr/share/man/man1/micro.1.gz
 
 `dpkg-reconfigure` can be used to update choices made during package installation.
+
     jyothisjagan@jyothisjagan:~$ sudo dpkg-reconfigure locales 
     [sudo] password for jyothisjagan: 
     Generating locales (this might take a while)...
@@ -74,6 +80,7 @@ Refer [apt-file](https://wiki.debian.org/apt-file)
     Generation complete.
 
 `dpkg -S <filename>` searches for filename from installed packages.
+
     jyothisjagan@jyothisjagan:~$ dpkg -S pthread.h
     libc6-dev:amd64: /usr/include/pthread.h
     autoconf-archive: /usr/share/doc/autoconf-archive/html/ax_005fpthread.html
@@ -82,6 +89,7 @@ Refer [apt-file](https://wiki.debian.org/apt-file)
 ## Dependencies 
 
 apt-cache rdepends mypackage will tell you packages that depends on mypackage
+
     jyothisjagan@jyothisjagan:~$ apt-cache rdepends rails
     rails
     Reverse Depends:
@@ -90,6 +98,7 @@ apt-cache rdepends mypackage will tell you packages that depends on mypackage
     passenger
 
 `reverse-depends -b <package>` shows reverse build dependencies
+
     jyothisjagan@jyothisjagan:~$ reverse-depends -b gedit
     Reverse-Build-Depends
     =====================
@@ -99,6 +108,7 @@ apt-cache rdepends mypackage will tell you packages that depends on mypackage
 ## Check Package Version 
 
 `apt policy <package>` shows the version of package which is installed or going to be installed.
+
     jyothisjagan@jyothisjagan:~$ apt policy vim
     vim:
       Installed: 2:8.1.0875-5
@@ -124,18 +134,22 @@ Refer [Packaging SourcePackage](https://wiki.debian.org/Packaging/SourcePackage)
 Let us install `bc` from source.
 
 First, get source package.
+
     apt source bc
 
 Let us check the contents of the current directory now.
+
     jyothisjagan@jyothisjagan:~/session3$ ls
     bc-1.07.1  bc_1.07.1-2.debian.tar.xz  bc_1.07.1-2.dsc  bc_1.07.1.orig.tar.gz
 
 Now we need to build the package.
+
     apt source -b bc
 
 If build dependencies are met, then it will generate .deb file.
 
 Note: You can install build dependencies using
+
     apt build-dep <package>
 
 ## Installing Packages from Third Party Repositories
@@ -143,12 +157,13 @@ Note: You can install build dependencies using
 Here, we are going to install libjs-pdf from https://people.debian.org/~praveen/gitlab/pool/main/p/pdf.js/
 
  1. Add the gpg public key(at https://people.debian.org/~praveen/gitlab/) as a trusted key.
+                                                                                                
     apt-key add praveen.key.asc
- 2. Add sources.list entry. For that we can download `gitlab.list` to `/etc/apt/sources.list.d`
- 3. 
 
-    apt update
-    apt install 
+ 2. Add sources.list entry. For that we can download `gitlab.list` to `/etc/apt/sources.list.d`. Then
+
+        apt update
+        apt install libjs-pdf
 
     
 
@@ -159,12 +174,12 @@ Refer [Instructions](https://backports.debian.org/Instructions/)
 Here, we are going to install geary.
  1. Add backports to your sources.list
 
-    deb http://deb.debian.org/debian buster-backports main
+        deb http://deb.debian.org/debian buster-backports main
 
  2. Run `apt-get update`
  3. Install the package from backports
 
-    apt-get -t buster-backports install geary
+        apt-get -t buster-backports install geary