Expert Shell Scripting by Ron Peters

By Ron Peters

Procedure directors desire libraries of options which are creative yet comprehensible. They don't are looking to reinvent the wheel, yet they don't are looking to reinvent filesystem administration both! specialist Shell Scripting is the final word source for all operating Linux, Unix, and OS X procedure directors who want to have brief, succinct, and robust shell implementations of difficult procedure scripting tasks.

* Automating small to medium procedure administration tasks
* studying method info and enhancing configuration files
* Scripting Linux, Unix, and OS X functions utilizing bash, ksh, et al.

Show description

Read or Download Expert Shell Scripting PDF

Best unix books

Red Hat Linux 7.2 Bible

Get step by step directions for making Linux install basic and painless; make yourself familiar with the Linux shell, dossier approach, and textual content editor; Use the XWindow method to customise your computer menus, icons, window supervisor, and xterm; Create and post formatted files with Linux functions; Get step -by-step directions for making Linux deploy uncomplicated and painless; achieve key approach management abilities together with establishing clients, automating method initiatives, backing up and restoring documents, and realizing the most recent protection concerns and threats.

The Complete Guide to the SAS Output Delivery System, Version 8

Utilize your SAS output! how you can generate technique output so you might view with an internet browser or that takes benefit of a excessive solution PostScript printer; flip the output of a method right into a SAS info set; switch the presentation of a procedure's effects to fit your personal wishes; and alter the colours and fonts that SAS makes use of in HTML and printer output.

A+ certification bible

Equipped round the examination goals for simple reference in the course of particular goal concentration, A+ Certification Bible includes huge self-evaluation possibilities that will help you confirm what components desire extra learn. accomplished insurance lets you maximize the knowledge, and tailor your research on your personal wishes at any point of expertise.

Systemprogrammierung in UNIX / Linux: Grundlegende Betriebssystemkonzepte und praxisorientierte Anwendungen

UNIX / Linux spielt heute in der Praxis eingesetzter Systemplattformen eine entscheidende Rolle. In diesem Buch finden Sie einen schnellen Einstieg in die Systemprogrammierung. Neben Grundlagen und Konzepten lernen Sie die wesentlichen Systemaufrufe kennen. Sie erfahren, wie UNIX / Linux aufgebaut ist und wie guy die Standardbausteine verwendet, um eigene Systemprogramme zu erstellen.

Extra info for Expert Shell Scripting

Sample text

Otherwise you have to add 13 to the month and subtract 1 from the year. The following code calculates the day value for today. Once you know this, you subtract the epoch value from that value to get the number of days since the start of the epoch. The script then outputs that value. The output is left unformatted in case you want to use the number as input for another command or process. today_days=$((($year*365)+($year/4)-\ ($year/100)+($year/400)+\ ($month*306001/10000)+$day)) days_since_epoch=$(($today_days-$epoch_days)) echo $days_since_epoch You may find it useful to have two versions of this script: one that outputs the elapsed time in days and the other that outputs it in seconds.

Thus, both expressions determine if a variable has been assigned a value. The following expressions are similar to the previous ones; they determine if a variable is undefined: if [ -z $string ];then... if [ ! $any_variable ];then... These conditional statements are simply the negations of the corresponding expressions in the previous examples (-z tests whether a string has zero length, and ! is the logical NOT symbol). The next example uses a couple of features, one of which we have already seen.

Once the last digit is found, the function returns a true value of 1 if the digit is an even number and a false of 0 if it is not. I will discuss this command and others like it in Chapter 24. \)$/\2/'` case $LAST_DIGIT in 0|2|4|6|8 ) return 1 ;; *) return 0 ;; esac } This second function is one I have used many times. It determines whether a remote system is running and connected to the network. It works by pinging the specified machine three times and sending the output to /dev/null. Success is based on the value of $?

Download PDF sample

Rated 4.46 of 5 – based on 22 votes