Sign In Start Free Trial
Account

Add to playlist

Create a Playlist

Modal Close icon
You need to login to use this feature.
  • Book Overview & Buying Linux Command Line and Shell Scripting Bible
  • Table Of Contents Toc
Linux Command Line and Shell Scripting Bible

Linux Command Line and Shell Scripting Bible - Third Edition

By : Richard Blum, Christine Bresnahan
close
close
Linux Command Line and Shell Scripting Bible

Linux Command Line and Shell Scripting Bible

By: Richard Blum, Christine Bresnahan

Overview of this book

The Linux command line enables you to type specific shell commands directly into the system to manipulate files and query system resources. Command line statements can be combined into short programs called shell scripts, a practice increasing in popularity due to its usefulness in automation. Linux is a robust system with tremendous potential, and Linux Command Line and Shell Scripting Bible opens the door to new possibilities. Linux Command Line and Shell Scripting Bible is your essential Linux guide. It contains new functional examples that are fully updated to align with the latest Linux features. Beginning with command line fundamentals, the book moves into shell scripting and shows you the practical application of commands in automating frequently performed functions. This book is a complete guide providing detailed instruction and expert advice working within this aspect of Linux. Whether used as a tutorial or as a quick reference, this book contains information that every Linux user should know.
Table of Contents (34 chapters)
close
close
2
Part I: The Linux Command Line
13
Part II: Shell Scripting Basics
20
Part III: Advanced Shell Scripting
28
Part IV: Creating Practical Scripts
32
End User License Agreement
2
Appendix B: Quick Guide to sed and gawk

Logging Messages

Sometimes, it's beneficial to send output both to the monitor and to a file for logging. Instead of having to redirect output twice, you can use the special tee command.

The tee command is like a T-connector for pipes. It sends data from STDIN to two destinations at the same time. One destination is STDOUT. The other destination is a filename specified on the tee command line:

 tee filename

Because tee redirects data from STDIN, you can use it with the pipe command to redirect output from any command:

 $ date | tee testfile
 Sun Oct 19 18:56:21 EDT 2014
 $ cat testfile
 Sun Oct 19 18:56:21 EDT 2014
 $

The output appears in STDOUT and is written to the file specified. Be careful: By default, the tee command overwrites the output file on each use:

 $ who | tee testfile
 rich     pts/0        2014-10-17 18:41 (192.168.1.2)
 $ cat testfile
 rich     pts/0        2014-10-17 18:41 (192.168.1.2)
 $

If you want to append data to the file, you must use the -a option:

 $ date...
CONTINUE READING
83
Tech Concepts
36
Programming languages
73
Tech Tools
Icon Unlimited access to the largest independent learning library in tech of over 8,000 expert-authored tech books and videos.
Icon Innovative learning tools, including AI book assistants, code context explainers, and text-to-speech.
Icon 50+ new titles added per month and exclusive early access to books as they are being written.
Linux Command Line and Shell Scripting Bible
notes
bookmark Notes and Bookmarks search Search in title playlist Add to playlist font-size Font size

Change the font size

margin-width Margin width

Change margin width

day-mode Day/Sepia/Night Modes

Change background colour

Close icon Search
Country selected

Close icon Your notes and bookmarks

Confirmation

Modal Close icon
claim successful

Buy this book with your credits?

Modal Close icon
Are you sure you want to buy this book with one of your credits?
Close
YES, BUY

Submit Your Feedback

Modal Close icon
Modal Close icon
Modal Close icon