UNIX 2 Enhancing your UNIX Skills Workbook February 2017 Associated Workbooks: UNIX 2: Practical Exercise - 3059-2016 UNIX 2: Solution - 3060-2016 Document Number: 3133-2016 1 Contents Chapter 1. Deeper UNIX Unix 1 - Revision .............................................................................................................................1 ssh and logout ............................................................................................................................1 files, directories and pathnames ...................................................................................................1 more and nano ...........................................................................................................................1 permissions ................................................................................................................................1 lpr, enscript, lpq and lprm ............................................................................................................1 Unix 1 - Revision .............................................................................................................................2 shells ..........................................................................................................................................2 filename completion (<tab>) .........................................................................................................2 history mechanism ......................................................................................................................2 * and ?........................................................................................................................................2 redirection ..................................................................................................................................2 foreground and background processes ........................................................................................2 UNIX environment.......................................................................................................................2 ftp...............................................................................................................................................2 Unix Philosophy ..............................................................................................................................3 What Is This Machine Actually Doing?..............................................................................................4 The Shell ....................................................................................................................................4 Default shell ................................................................................................................................4 Note for the deranged .................................................................................................................4 What Is A Unix Program? ................................................................................................................6 How The Shell Interprets Input .........................................................................................................8 Shell metacharacters ..................................................................................................................8 Geek note ...................................................................................................................................8 What Can I Do With Metacharacters? ..............................................................................................9 Wildcards * ? []............................................................................................................................9 Home directory ~ ........................................................................................................................9 Dereferencing variables $ ............................................................................................................9 Comment # .................................................................................................................................9 Alternatives {} ........................................................................................................................... 10 Redirection of input and output < > ............................................................................................ 10 Quoting \ ’ " ............................................................................................................................... 10 Command separators ; & ‘ ......................................................................................................... 10 Backquotes ................................................................................................................................... 11 How The Shell Finds Commands ................................................................................................... 12 Writing Your Own Commands ................................................................................................... 13 Shell Scripts ............................................................................................................................. 14 Running A Shell Script ................................................................................................................... 15 Sourcing ................................................................................................................................... 15 Note from the old-timers ............................................................................................................ 15 Bash Shell Startup Files ................................................................................................................ 16 The Environment ........................................................................................................................... 17 Environment Passing..................................................................................................................... 18 More on child processes............................................................................................................ 18 Relative note............................................................................................................................. 18 Running Multiple Programs ............................................................................................................ 20 Processes And Running Commands .............................................................................................. 21 Foreground And Background ......................................................................................................... 23 Job and Process Control ............................................................................................................... 24 Killing Off Jobs And Processes ...................................................................................................... 26 Summary Of Deeper Unix .............................................................................................................. 27 Chapter 2. Power UNIX Regular Expressions ..................................................................................................................... 28 Regexps - Literals And Anchors ..................................................................................................... 29 Regexps - Character Classes ........................................................................................................ 31 Regexps - The * Quantifier And \ ................................................................................................... 33 More On Grep .............................................................................................................................. 34 SED Addresses ............................................................................................................................ 37 SED Functions ............................................................................................................................. 38 SED - Substitution ........................................................................................................................ 39 Finding Files ................................................................................................................................. 42 Find Actions ................................................................................................................................. 43 Sort .............................................................................................................................................. 44 Filters ........................................................................................................................................... 45 Summary Of Power Unix ............................................................................................................... 47 Chapter 3. UNIX toolkit A Swiss Army Knife Of Commands................................................................................................ 48 Examining An Unknown File ......................................................................................................... 49 More On Files ..............................................................................................................................