presentation.tex

%!TEX TS-program = xelatex
% Standard Pattern
% program name in texttt
% program function and syntax
% program example by person giving the talk
% program useful options
% program example for participants

\documentclass[11pt]{beamer}

\usetheme{minflat}

\usepackage{hyperref}
\hypersetup{pdfstartview={Fit}}
\usepackage{booktabs}

\title[PLUG Meetup]{Master your Command Line \\ \small{(Before it masters you)} }
\subtitle{\large{Important terminal commands}}
\author{Tejas Sanap}
\date{\today}


\begin{document}
	\begin{frame}
		\titlepage
	\end{frame}
	\begin{frame}
		\tableofcontents
	\end{frame}

	\section{Introduction}
		\begin{frame}{UNIX Philosophy}
			Focused on \emph{modularity} \& \emph{reusability}. \\
			It can be summarized as:
			\begin{itemize}
				\item Write programs that do one thing and do it well.
				\item Write programs to work together.
				\item Write programs to handle text streams, because that is a universal interface.
			\end{itemize}
		\end{frame}

		\begin{frame}{Basic Operations}
			\begin{itemize}
				\item Search for text (in files).
					\begin{itemize}
						\item \texttt{cat, head, tail, wc}
						\item \texttt{grep}
					\end{itemize}
				\item Search for files (in directories).
					\begin{itemize}
						\item \texttt{ls}
						\item \texttt{find, locate}
					\end{itemize}
				\item Manipulate files and directories.
					\begin{itemize}
						\item \texttt{cp, scp, rm, mv}
						\item \texttt{rsync}
					\end{itemize}
			\end{itemize}			
		\end{frame}

		\begin{frame}{GNU Coreutils}
			The {\textbf{\color{darkpurple}{GNU Core Utilities} } } are the basic file, shell and text manipulation utilities of the GNU operating system. \\
				They are expected to be present on every operating system. \\
				Previously, the core utilities were implemented by the following pacakages:
				\begin{enumerate}
				  \item \texttt{fileutils} 
				  \item \texttt{shellutils} 
				  \item \texttt{textutils}
				\end{enumerate}	
				In 2003, these three packages were combined into the current \texttt{coreutils} package.
		\end{frame}

		\begin{frame}{Globbing}
			\begin{itemize}
				\item \textbf{Glob} is the common name for a set of Bash features that match or expand specific types of patterns. 
				\item When used for filename matching globs are called \textbf{wildcards}.
				\item Wildcards cannot match filenames that \textbf{don't yet exist}.
			\end{itemize}
			\begin{align*}
				\begin{tabular}{cl}
					\toprule
					\textbf{Glob} & \textbf{Meaning} \\
					\midrule
					\textbf{*} & matches all characters, any number of times \\
					\textbf{?} & matches all characters, but only once \\
					\textbf{[...]} & character class \\
					\textbf{\{... , ... , ...\}} & group patterns seperated by comma's \\
					\bottomrule
				\end{tabular}
			\end{align}
			\begin{exampleblock}{Example}
				\texttt{\$ for each in "\$(ls -d /*)"; \\ do (cd \$each \&\& mv ?? ../ \&\& cd -); done }
			\end{exampleblock}
		\end{frame}

		\begin{frame}{regex}
			A few simple regex characters:
			\begin{align*}
				\begin{tabular}{cl}
					\toprule
					\textbf{Character} & \textbf{Meaning} \\
					\midrule
					\textbf{\string^} & Beginning of line \\ 
					\textbf{\$} & End of line \\
					\textbf{.} & Single character \\
					\textbf{*} & All characters \\
					\textbf{\{n,m\}} & Occurance between minimum \emph{n} and maximum \emph{m} times
					\endrule
				\end{tabular}
			\end{align}
		\end{frame}

	\section[File]{Inside the file}

			\begin{frame}{\texttt{cat, head, cd , wc}}
				Utilities to view file content
				\begin{example}
					\texttt{cat -A -n -s torrent-trackers}
				\end{example}
				\begin{example}
					\texttt{head -n 10 torrent-trackers}
				\end{example}
				\begin{example}
					\texttt{cd , cd .., cd \textasciitilde, cd -}
				\end{example}
				\begin{example}
					\texttt{wc torrent-trackers}
				\end{example}
				{
					\definecolor{beamerorange}{RGB}{255,0,0}
					\begin{alertblock}{\texttt{wc} - Output}
						\texttt{465  233 9585 torrent-trackers} \\
						\tiny \texttt{newline, wordcount, bytes, filename}
					\end{alertblock}
				}
			\end{frame}

			\begin{frame}{\texttt{grep}}
				\texttt{grep} prints line that matches a certain pattern.
				\begin{alertblock}{Syntax}
					\texttt{grep OPTIONS PATTERN INPUT\_FILE\_NAMES}
				\end{alertblock}
				\begin{exampleblock}{Example}
					\begin{semiverbatim}
						\$ grep --color=always "anime" torrent-tracker
						udp://tc.{\textbf{\color{red}{anime} } }reactor.ru:8082/announce
						udp://tc.{\textbf{\color{red}{anime} } }reactor.ru:8082/announce 
					\end{semiverbatim}	
				\end{exampleblock}
			\end{frame}

			\begin{frame}[t, fragile]{\texttt{grep}}
				The exit status of \texttt{grep} when:
				\begin{itemize}
					\item \textbf{line is selected} is \textbf{0}.
					\item \textbf{no line is selected} is \textbf{1}.
					\item \textbf{an error occurs} is \textbf{2}.
				\end{itemize}
				Useful \texttt{grep} options:
				\begin{description}
					\item[ \texttt{-i}] ignore case
					\item[ \texttt{-v}] invert matches
					\item[ \texttt{-c}] count no. of matching lines
					\item[ \texttt{-n}] prefix each line with line number
					\item[ \texttt{-l}] print name of the file and suppress all other output
					\item[ \texttt{-H}] print filename for each match
					\item[ \texttt{-o}] print only the matched parts of a line
					\item[ \texttt{-s}] suppress error messages
					\item[ \texttt{-a} ] accept binary input
					\item[ \texttt{--label=LABEL}] display input coming from \texttt{stdin} as input from file \texttt{LABEL}
					\item[ \texttt{-A, -B, -C}] print \texttt{n} lines after, before or around the matching line
				\end{description}
			\end{frame}

			\begin{frame}[t]{\texttt{grep}}
				\begin{block}{Task}
					\begin{enumerate}
						\item We have a tar file named \texttt{python\_code.tar.gz}
						\item We want to search for a function named \texttt{main}
						\item But, without, extracting or decompressing the tar file
					\end{enumerate}
				\end{block}	
				\setbeamercovered{invisible}
				\begin{example}
					\begin{semiverbatim}
						\only<1>{\$ tar -xf python\_code.tar.gz}
						\only<2>{\$ tar -xzf python\_code.tar.gz}
						\only<3>{\$ tar -xzf python\_code.tar.gz --to-command='\textbf{\color{red}{grep main}}'}
						\only<4>{\$ tar -xzf python\_code.tar.gz --to-command='\textbf{\color{red}{grep -a main}}'}
						\only<5>{\$ tar -xzf python\_code.tar.gz --to-command='\textbf{\color{red}{grep -a -H main}}'}
						\only<6>{\$ tar -xzf python\_code.tar.gz --to-command='\textbf{\color{red}{grep -a -H --label="\$TAR\_FILENAME" main}}'}
						\only<7>{\$ tar -xzf python\_code.tar.gz --to-command='\textbf{\color{red}{grep -a -H --label="\$TAR\_FILENAME" -n main}}'}
						\only<8>{\$ tar -xzf python\_code.tar.gz --to-command='\textbf{\color{red}{grep -a -H --label="\$TAR\_FILENAME" -c main}}'}
						\only<9>{\$ tar -xzf python\_code.tar.gz --to-command='\textbf{\color{red}{grep -a -H --label="\$TAR\_FILENAME" -c -s main}}'}
					\end{semiverbatim}
				\end{example}
			\end{frame}


	\section[Directory]{Inside the directory}

			\begin{frame}{ \texttt{ls}}
				\texttt{ls} displays directory contents. \\
				Useful \texttt{ls} options:
				\begin{description}
					\item[ \texttt{--sort}] \texttt{-S, -t, -X} Size, time, extension
					\item[ \texttt{--format}] \texttt{-1, -m, -l} Horizontal, commas, long
					\item[ \texttt{-h}] human readable
					\item[ \texttt{-g}] don't display file owner
					\item[ \texttt{-G}] don't display file group
					\item[ \texttt{-d}] if argument is a directory, list only its name 
					\item[ \texttt{-I}] Ignore files matching pattern
					\item[ \texttt{--hide}]  Hide files matching pattern (overriden by \texttt{-a})
				\end{description}
			\end{frame}


			\begin{frame}{ \texttt{ls}}
				\begin{block}{Task}
					\begin{enumerate}
						\item List all the directories in the folder \texttt{find}
						\item List the last five files/folders to be modified
					\end{enumerate}
				\end{block}	
				\setbeamercovered{invisible}
				\begin{example}
					\begin{semiverbatim}
						\only<1>{\$ ls       }
						\only<2>{\$ ls -d */}
						\only<3>{\$ ls -1t | head} \end{semiverbatim}	
				\end{example}
			\end{frame}


			\begin{frame}[fragile]{ \texttt{find}}
				\texttt{find} search for files in a directory hierarchy.
				\setbeamercovered{invisible}
				\begin{alertblock}{Syntax}
					\only<1>{\texttt{find DIRECTORY EXPRESSION}}
					\only<2->{\texttt{find DIRECTORY TESTS ACTIONS}}
				\end{alertblock}
				\only<3->{
				\begin{example}
					\begin{semiverbatim}
						\$ find . -name file1b1
					\end{semiverbatim}					
				\end{example}
				}
				\only<4->{
					Useful global options:
					\begin{description}
						\item[ \texttt{-maxdepth n}] Descend at most \texttt{n} levels
						\item[ \texttt{-mindepth n}] Do not apply tests at levels less than \texttt{n}
					\end{description}
				}
			\end{frame}

			\begin{frame}{ \texttt{find}}
				Following \texttt{TESTS} are available:
				\begin{description}
					\item[Name] \texttt{-name, -iname, -path, -ipath}
					\item[Links]
					\item[Time] \texttt{-atime, -ctime, -mtime, -amin, -cmin, -mmin, -anewer, -cnewer, -mnewer, -newerXY, -used}
					\item[Size] \texttt{-size, -empty}
					\item[Type] \texttt{-type}
					\item[Owner] \texttt{-user, -group}
					\item[Mode Bits/ File Permissions] \texttt{-perm, -readable, -writable, -executable}
					\item[Contents]
					\item[Directories]
					\item[Filesystems]
				\end{description}
			\end{frame}

			\begin{frame}[fragile]{ \texttt{find -TESTS}}
				\only<1>{
				\begin{exampleblock}{ \texttt{-path}}
					\begin{semiverbatim}
\$ find . -path '*/dir4a'

./dir1/dir1a/dir2c/dir3a/dir4a \end{semiverbatim}	
				\end{exampleblock}
				\begin{exampleblock}{ \texttt{-size}}
					\begin{semiverbatim}
\$ find . -size +5k

\$ find . -size -5k
\end{semiverbatim}	
				\end{exampleblock}
				\begin{exampleblock}{find files with some content}
					\begin{semiverbatim}
\$ find . -name '*.[23]' | xargs grep -l anime

./dir1/dir1a/dir2c/dir3a/file4.2

./dir1/dir1b/file1b.3
\end{semiverbatim}	
				\end{exampleblock}
				}
				\only<2-3>{
					\begin{block}{Task}
						Find files that were edited before:
						\begin{enumerate}
							\item 10 days.
							\item 10 minutes.
						\end{enumerate}
					\end{block}
				}
				\only<3>{
					\begin{exampleblock}{ \texttt{-newerXY}}
						\begin{semiverbatim}
\$ find . -newermt "Jul 11"
\end{semiverbatim}	
					\end{exampleblock}
					\begin{exampleblock}{ \texttt{-newerXY}}
						\begin{semiverbatim}
\$ find . -newermt "10:20"
\end{semiverbatim}	
					\end{exampleblock}
				}
				\only<4-5>{
					\begin{block}{Task}
						Find and delete all files of a specific file type.
					\end{block}
				}
				\only<5>{
					\begin{exampleblock}{ \texttt{-regex}}
						\texttt{\$ find -regextype egrep -regex ".*\.(db|jpg)"}
					\end{exampleblock}
					\begin{exampleblock}{Use multiple tests}
						\texttt{\$ find . -type f \backslash ( -name "*.db" -or -name "*.jpg" \backslash ) }
					\end{exampleblock}
				}
			\end{frame}

			\begin{frame}{ \texttt{find -ACTIONS}}
				\begin{alertblock}{Syntax}
					\only<1>{
						\texttt{ -execdir command {\color{red}\{\}} ';'} \\
						\tiny \hspace{3.2cm} { \color{red} \texttt{file name} }
					}
					\only<2>{
						\texttt{ -execdir command \{\} {\color{red}';'} } \\
						\tiny \hspace{3.6cm} { \color{red} \texttt{end of command} }
					}
				\end{alertblock}	
				\begin{exampleblock}{ \texttt{-execdir}}
					\texttt{\$ find -name "*.db" -execdir rm \{\} ';'}
				\end{exampleblock}				
			\end{frame}

			\begin{frame}[fragile]{ \texttt{locate}}
				\texttt{locate} finds files by name. \\
				It has two drawbacks:
				\begin{enumerate}
					\item It uses the database built using \texttt{updatedb}.
					\item It does not check if the files still exist.
				\end{enumerate}
				Useful \texttt{locate} options:
				\begin{description}
					\item[ \texttt{-l, --limit}] limit the no. of entries being displayed
					\item[ \texttt{-b, --basename}] match only the basename of the file
					\item[ \texttt{-S, --statistics}] display the database stats
				\end{description}
				\begin{exampleblock}{Example}
					\begin{semiverbatim}
\$ sudo updatedb
\$ locate \end{semiverbatim}
				\end{exampleblock}
			\end{frame}
	
	\section[Manipulate]{Manipulate Files and Directories}

		\begin{frame}{ \texttt{rsync}}
			 Rsync is a fast and  extraordinarily  versatile  file  copying  tool.

			 \texttt{cp} and \texttt{mv} have the following drawbacks:
			 \begin{enumerate}
			 	\item Don't show progress bars
				\item Don't support incremental file copying/backups
				\item Don't support various secure protocols
				\item Don't have "resume" copying/moving capability
			 \end{enumerate}

			 However, to use \texttt{rsync} it must be installed on both source and destination machines.
		\end{frame}

		\begin{frame}{ \texttt{rsync}}
			Useful options for \texttt{rsync}:
			\begin{description}
				\item[ \texttt{-a}] archive mode
				\item[ \texttt{-z}] compress files
				\item[ \texttt{--dry-run}] perform a trial without making any changes
				\item[ \texttt{--delete}] delete files that aren't present in the source directory
				\item[ \texttt{--delete-from-source}] move files
				\item[ \texttt{-e}] give SSH options
				\item[ \texttt{-v}] show verbose output
			\end{description}
		\end{frame}

	\section[Bling]{Customize your shell}

		\begin{frame}{\texttt{fortune} \& \texttt{cowsay}}
			\begin{itemize}
				\item Let's add some star trek quotes
				\item fortune
				\item Cowthink and cowsay
			\end{itemize}
		\end{frame}

	\section{References}

		\begin{frame}{References}
			\begin{enumerate}
				\item \href{http://find.unixpin.com/}{UnixPin}
				\item {
						\texttt{glob}:
						\begin{enumerate}
							\item \texttt{man 7 glob}
							\item \texttt{man 7 regex}
						\end{enumerate}
					}
				\item {
						\texttt{find}:
						\begin{enumerate}
							\item \href{http://doc.cat-v.org/unix/find-history}{Find History}
							\item GNU Findutils - \texttt{info} --> Find
						\end{enumerate}
					}
			\end{enumerate}
		\end{frame}

	\highlightedFrame{Questions?}

\end{document}

% vim: set foldmethod=manual