introduction to unix shell scripting pdf

... file into stdin, file descriptor 0 We process the file using a while loop and then reset the file descriptor 0 back to its default File descriptors are really not too hard to use after scripting ... file descriptor 3 Onmost Unix systems valid file descriptors range from 0 to 19 In our case we are going touse file descriptor 3, but we could have just as easily used file descriptor 5 There ... example we used two file descriptors We can also use other filedescriptors to handle file input and storage In our next four timing functions we aregoing to use file descriptor 0 (zero), which is standard

Ngày tải lên: 09/08/2014, 16:20

... modify the shell script in Listing 16.8 to add a command-line parameter to let you control queuing and printing individually from the same shell. .. Now we need to combine the shell scripts ... desk or write a shell script to monitor the printer queues and reenable the queues as they drop offline. I prefer the second method. Like every other Systems Administrator, I like to be proactive ... thing to create a shell script that only enables queuing, as shown in Listing 16.10 423 424 Chapter 16 #!/bin/ksh... technique in a shell script to redirect the failure notification to a log

Ngày tải lên: 09/08/2014, 16:20

... Trang 2• Introduction to Unix and its architecture• Learn to use basic Unix commands • Learn to use vi editor • Learn to write shell scripts • Learn to register and run shell scripts from ... –lrt, myshell.sh oracle$1 to $9 – will give the arguments 1 to 9 To get remaining we need to use shift command. $@ - will give the complete list of all the arguments to that shell Trang 25$? - returns ... a shell script should start with a line: #!/bin/ksh Example shell script #!/bin/bash echo “Hello $USER” echo “Today is “ `date` echo “You are in directory $PWD” exit 0 Trang 21Ex: ls –lrt, myshell.sh

Ngày tải lên: 24/10/2014, 10:53

... occasionally refers to it, but only reluctantly It also suffers from having attracted too much attention thirty years ago One or several texts are usually recommended: the ‘‘Introduction to Commutative ... with fields I had to develop quite a lot of language new to them, but I have been careful to articulate all chapters around at least one important theorem Furthermore I have tried to stimulate readers, ... myself to refer to some of those All chapters are followed by a series of exercises Many are easy and a few are more intricate; readers will have to make their own evaluation! I would like to thank

Ngày tải lên: 22/03/2014, 15:21

... Connector architecture, each App server has to provide an proprietary adaptor for each EIS system  m (# of App servers) x n (# of EIS's) Adaptors  With Connector architecture, same adaptor works ... communication systems  Point-to-Point, Publish and Subscribe  JMS defines standard Java APIs to messaging systems Trang 24Connector Architecture Trang 25Connector Architecture  Defines standard ... Naming and Directory Interface  Utilized by J2EE applications to locate resources and objects in portable fashion  Applications use symbolic names to find object references to resources via

Ngày tải lên: 31/03/2014, 20:20

... S is large, since there would be no payoff, it cannot be worthwhile to exercise an American put; it is optimal to hold on to the option. On the other hand, in the limit S → 0, the payoff from ... optimal to exercise. Interpolating between these two extremes, we might expect there to be a well-defined optimal exercise boundary, S  (t), such that • for S(t)<S  (t) it is optimal to exercise, ... expressed as P Am (S 0 , 0) = sup 0≤τ ≤T E  e −rτ (S(τ))  , (18.8) where τ is a stopping time.Todefine a stopping time precisely requires technic- alities that have not been developed in this

Ngày tải lên: 21/06/2014, 04:20

... steady The new temperature is foundto be about 76.0 C To the second flask we add 25 g of water, ato 20 C, and find the final temperature to be about 82.2 C We musto o ask now whether the experiment ... water tell us that something passes from the fire or hot coil to nearby objects (specifically to us or to the pan of water) The effect is to “heat” the objects, by which we mean that there is a sensation ... familiar with atoms and molecules, it may be surprising to find how far one can go toward treating chemical and physical equilibria without employing any simplified models or delving into theories

Ngày tải lên: 08/08/2014, 15:21

... unit of mass, to move a mass between two points The gravitational potential difference for a well is positive if the top is measured with respect to the bottom, or negative if the bottom is measured ... solution to the equation 2.51 x 10 (5 - 2x) = 27x 6 2 3 Because K is large, the reaction must be shifted well to the right, so x will be nearly equal to 5/2,eq and 5 - 2x will be very sensitive to ... with respect to 0.5 Then This answer confirms the assumption that taking s negligible with respect to 0.5 gives a self-consistent, and therefore mathematically valid, solution to the problem

Ngày tải lên: 08/08/2014, 15:21

... set of data to display we need to do a little math.This is not too difficult when you take one step at a time In this shell script let’s use a file to store the command output data To refresh ... entries to look like? How are we going to handle the wrong entry type? The entries need to conform to the specific test type the script is looking for The best way to handle this is to require ... also going to do things a little differently because this is a learning process As we all know, there are many ways to accomplish the same task in Unix;shell scripting is a prime example To make

Ngày tải lên: 09/08/2014, 16:20

... piped to the next... shown to the user based # on the Unix operating system that this shell script is # executing on Different Unix flavors have differing # outputs and the fields vary too ... there is to the iostat shell script Let’s now move on to the vmstat solution Using vmstat to Measure the System Load The vmstat shell script uses the exact same technique as the iostat shell ... that we use a single case statement to set up the environment for the shell script to run the correct iostat command for each of the four Unix flavors. If the Unix flavor is not in the list, then

Ngày tải lên: 09/08/2014, 16:20

... can utilize to build a very nice tool to monitor your systems and appli- cations Always start with a ping! If the box is unpingable, then your first job is to get the machine booted or to call hardware ... since Iput this tool in place The key is to keep the business in business, and the best way to applica-do that is to be very proactive This is where good monitoring and control shell scriptsmake ... going to use the modulo arithmetic operator to reduce all numbers to a fixed set of numbers between [0 N-1], which is called modulo N arithmetic We are going to use this pseudo-random number to

Ngày tải lên: 09/08/2014, 16:20

... you have a problem. To resolve this issue, define a new file to point to the PINGLIST variable, and then we will use the file to store the ping list data instead of a variable. To use PINGLIST as ... be overkill for any large shop, but it is easy to modify the shell script to accomplish this task. You want to make the following change to the shell script after completing the tasks in the ... function to execute the correct command syntax for the specific operating system. The uname command is a very useful tool for shell scripting solutions for various Unix flavors in a single shell

Ngày tải lên: 09/08/2014, 16:20

... want to store the file on the system? I like touse a separate variable to hold the directory name With two separate variables repre-senting the directory and filename, you can move the log directory ... instance we have users that you want to monitor the entire monitor-session In the next situation you want to monitor activity only when a user wants root access to the system Our systems have direct, ... directory to start the search.This adds a little more flexibility to the shell script 2 Each time we run the findlarge.ksh shell script, we overwrite the $OUTFILE You may, however, want to keep

Ngày tải lên: 09/08/2014, 16:20

... added to this shell script. The my_program function is used to point to the program or shell script that needs all of these unique filenames. It is better to point to an external program or shell ... shell script SCALE=”0” # Initialize the scale value to zero NUM_LIST= # Initialize the NUM_LIST variable to NULL COUNT=0 # Initialize the counter to zero MAX_COUNT=$# # Set MAX_COUNT to the total ... but to be safe we need to do a sanity check for any duplicate numbers. 540 Chapter 21 When we get a unique number we are ready to put the new filename together. We have three variables that together

Ngày tải lên: 09/08/2014, 16:20

... the shell script echo $RESULT Other Options to Consider As with all of the scripts in this book, we can always make some changes to any shellscript to improve it or to customize the script to ... protocol. Trang 16Adding Groups to the Basic CodeThe code segment in Listing 25.1 forms the basis for the entire shell script We are going tobuild on the base code to allow us to send messages to ... we are going to look at a technique to send pop-up messages toWindows desktop using Samba See you in the next chapter! Trang 12I really like this shell script, and I use it a lot to tell my users

Ngày tải lên: 09/08/2014, 16:20

... the stiffness is insufficient torestore the unbent shape, so that the beam is beginning to buckle Equation 10 will be satisfied by functions that are proportional to their own second derivatives ... y about the neutralaxis The parameter Q(y) is notorious for confusing persons new to beam theory To determine itfor a given height y relative to the neutral axis, begin by sketching the beam ... tangent to the initialstraight-line portion of the load-deflection curve, N/mm of deflection 9 A rectangular beam is to be milled from circular stock as shown What should be theratio of height to

Ngày tải lên: 11/08/2014, 09:21

... vary from system to system — see the man pages University Technology Services In the Introduction to UNIX document 3 ã shell programming ã Unix command summary tables ã short Unix bibliography ... Services Directory Navigation and Control Commands 20–22 pwd print working directory cd change working directory (“go to directory) mkdir make a directory rmdir remove directory University ... the user ã e.g. vt100, xterm or sun ã To reset: ã setenv TERM terminaltype (C -shell) ã may need to unsetenv TERMCAP ã TERM= terminaltype ; export TERM (Bourne shell) University Technology Services ...

Ngày tải lên: 07/11/2013, 10:15