Shell Scripting Recipes [electronic resource] :  A Problem-Solution Approach /
Johnson, Chris.author.
Varma, Jayant.author.
Filled with over 150 essential, practical recipes that empower Unix users to regain lost time spent creating and testing shell scripts. The majority of scripts included are POSIX-compliant and supported by many of the major shell variants, including Bash, ksh, and sh. Each real-world example recipe follows the same problem-solution structure, meaning cross-referencing is easy and fast. Recipe topics include file conversion (DOS, UNIX, and Mac), system administration, resource monitoring, filename management, complex date calculations, screen control capabilities, and much more. Completely updated for this second edition and taking all the changes of the past ten years into account, every recipe in this book is now relevant for a modern audience. Authors Chris Johnson’s and Jayant Varma’s code is clear, direct, and applicable. Add this excellent reference to your library today.
Description based upon print version of record.
Contents at a Glance; Contents; About the Authors; Acknowledgments; Chapter 1: The POSIX Shell and Command-Line Utilities;  Shell Commands;  echo ;  printf ;  set ;  shift ;  type ;  getopts ;  case ;  eval ;  local ;  Parameters and Variables;  Positional Parameters ;  Special Parameters ; Shell Variables;  standard-vars-A Collection of Useful Variables;  Patterns;  Pathname Expansion ;  Regular Expressions ;  Parameter Expansion;  The Bourne Shell Expansions ; {var:-DEFAULT}; {var:=DEFAULT}; {var:+VALUE}; {var:?MESSAGE};  POSIX Parameter Expansions
{#var}-Length of Variable's Contents{var%PATTERN}-Remove the Shortest Match from the End; {var%%PATTERN}-Remove the Longest Match from the End; {var#PATTERN}-Remove the Shortest Match from the Beginning; {var##PATTERN}-Remove the Longest Match from the Beginning; Combining Expansions;  Shell-Specific Expansions, bash2, and ksh93 ; {var//PATTERN/STRING}-Replace All Instances of PATTERN with STRING; {var:OFFSET:LENGTH}-Return a Substring of var;  Shell Arithmetic ;  Aliases ;  Sourcing a File ;  Functions;  Functions Are Fast ;  Command Substitution Is Slow
Using the Functions in This Book  standard-funcs: A Collection of Useful Commands;  1.1 get_key-Get a Single Keystroke from the User ; How It Works; Usage; The Script; Notes;  1.2 getline-Prompt User to Enter a Line ; How It Works; Usage; The Script;  1.3 press_any_key-Prompt for a Single Keypress ; How It Works; Usage; The Script;  1.4 menu1-Print a Menu and Execute a Selected Command ; How It Works; Usage; The Script;  1.5 arg-Prompt for Required Argument If None Supplied ; How It Works; Usage; The Script;  1.6 die-Print Error Message and Exit with Error Status ; How It Works; Usage
The Script 1.7 show_date-Display Date in D[D] MMM YYYY Format ; How It Works; Usage; The Script;  1.8 date_vars-Set Date and Time Variables ; How It Works; Usage; The Script;  1.9 is_num-Is This a Positive Integer? ; How It Works; Usage; The Script; Notes;  1.10 abbrev_num-Abbreviate Large Numbers ; How It Works; Usage; The Script; Notes;  1.11 commas-Add Thousands Separators to a Number ; How It Works; Usage; The Script;  1.12 pr1-Print Arguments, One to a Line ; How It Works; Usage; The Script;  1.13 checkdirs-Check for Directories;  Create If Necessary ; How It Works; Usage; The Script
1.14 checkfiles -Check That a Directory Contains Certain FilesHow It Works; Usage; The Script;  1.15 zpad-Pad a Number with Leading Zeroes ; How It Works; Usage; The Script;  1.16 cleanup-Remove Temporary Files and Reset Terminal on Exit ; How It Works; Usage; The Script;  The Unix Utilities;  cat: Concatenate Files to the Standard Output ;  sed: A Text Stream Editor ;  awk: Pattern Scanning and Processing Language ;  grep: Print Lines Matching a Regular Expression ;  date: Show or Set the System Date ;  tr: A Character Translation Utility ;  wc: Count Characters,Words, and Lines in a File
file: Determine the File Type
Includes bibliographical references and index.
Filled with over 150 essential, practical recipes that empower Unix users to regain lost time spent creating and testing shell scripts. The majority of scripts included are POSIX-compliant and supported by many of the major shell variants, including Bash, ksh, and sh. Each real-world example recipe follows the same problem-solution structure, meaning cross-referencing is easy and fast. Recipe topics include file conversion (DOS, UNIX, and Mac), system administration, resource monitoring, filename management, complex date calculations, screen control capabilities, and much more. Completely updated for this second edition and taking all the changes of the past ten years into account, every recipe in this book is now relevant for a modern audience. Authors Chris Johnson’s and Jayant Varma’s code is clear, direct, and applicable. Add this excellent reference to your library today.
Open source software.
Computer programming.
Software engineering.
Open Source.
Software Engineering/Programming and Operating Systems.