اريد المساعده في حل بعض الاسئله التي لا يعجركم حلها
السلام عليكم ورحمة الله وبركاته
عندما بحثت عند مساعده في حل هذه الاسئله قيل لي ان جوابها لن يكون الا عند مرتادين هذا المنتدى الرائع.
لقد حاولت اجابت تعضها على قدر معلوماتي المتواضعه و واجهت صعوبه في اجابت بقيتها.
لهذا سوف اطرح جميع الاسئله مع التي اجبتها فلربما كنت مخطأ في بعضها فتنبهوني عن خطائ.
Q1. These questions test you overall understanding of how files and directories are structured in UNIX .
A) UNIX may be considered a hierarchical file system, using directories to organize files. Consider a simple structure that consists of a directory called "/" or "root" that contains the three directories named "bin", "usr" and "export". Within "usr" there are a further two directories named "local" and "tmp". Draw the hierarchical structure of the directories described.
B) Due to the popularity of Microsoft operating systems for home PCs, most people are familiar with the notion of drive letters (e.g., "C:"). However, in UNIX systems these drive letters are absent. In UNIX multiple drives may exist, but the physical distribution of these drives is hidden from the user. To make distinct drives available in Windows we must "map" them to a drive letter. What is the term used (equivalent to "map") in UNIX when we describe the process of making drives available?
Mount
Q2. These questions test your understanding of how to navigate a UNIX file system .
A) Identify the UNIX command required to carry out following instructions:
i) List contents of current directory.
ls -la
ii) Move into directory "/usr/local".
cd usr/local
iii) Print on screen the current directory (the directory that you are in).
pwd
iv) Remove all files in the directory "/tmp"
rm /tmp/*
B) Identify the UNIX command to carry out the following instructions:
i) Make a directory called "hello" as a sub-directory of the current directory.
mkdir hello
ii) Remove the just created directory "hello"
rmdir hello
iii) Create a file named "myFile" in the current directory.
touch myFile
iv) List the contents of the current directory ensuring that all Directories in the listing are identified.
C) The use of wildcards is commonplace in UNIX. Describe, with an example, the function of the following wildcards:
i) *
ii) ?
Q3. These questions test your knowledge of access privileges .
A) What are the main distinct access groups that can be associated with a file/directory
.
Three types: u-- user, g -- group, a-- everyone
B) Write the command to change the privileges of the file "myFile" so everyone can read it, only user may write to it and no user may execute it.
chmod a+r myFile; chmod a-x-w myFile; chmod u+w myFile
Q4. These questions test your knowledge of environmental variables .
A) What useful purpose do the environments variables $PATH and $HOME provide?
B) Write the command to amend (not simply replace) the directory "/usr/local/bin" to your PATH.
C) Write the command to change the default editor to "nedit".
Q5 These questions test your ability to manipulate processes
.
A) Write the command that displays all process information on the current machine.
ps -a
B) Write the command that removes the process with the name "netscape" and process ID "491".
for netscape,use "Ctrl + c"; for ID491,use "kill 491"
C) Write the command that redirects the list of all processes on the machine to a file called "myProcessFile".
Q6. These questions allow you to demonstrate your ability to use scripts (bourne shell) .
A) Write a script that provides a file, "MyFiles", that contains a list of all the files in the current directory and displays on the screen the number of files present in the current directory.
B) Write a script that moves all the files that end in ".txt" from the current directory to another (target) directory. The target directory should be identified via a parameter passed to the script. This script should also produce a text file ("filesCopied") that lists all files that have been moved.
C) Write a script that reads in ten numbers (either one at a time during script execution or as parameters) and prints to the screen the sum of these numbers (hint - you may need to check out the "read" command).
D) Alter the previous script to allow it to work for arbitrary lists of numbers.
شاكرا لكم تعاونكم
جرب أعملهم لوحدك .. مافي صعوبة فيهم ..