pwd.txt

3. Redo the previous command, and this time redirect the output of the command into the file pwd.txt in the current directory (just as you did in Assignment #02).

   Hint: Recall that you can redirect into a file any output that appears on your terminal screen. You did this using the date command to create the file date.txt in Assignment #02.

4. Move (rename) the pwd.txt file from the current directory (Assignments) down into your Base Directory using the shortest relative pathname to do the move. (You did work similar to this in Section 4 of Worksheet #03 HTML.) Remember this relative pathname.

5. Use a command that shows file names to confirm that there are no files left in the current Assignments directory. (You will only see the directory basename of the Base Directory in the current directory.)

6. Use the echo command to display on your terminal screen the relative pathname that you just used as the second argument to the previous move command.

   Hint: Redo the move command with the move command name and the first argument replaced by echo so that only the second pathname echoes to the terminal screen. Do not include the first pathname.

echopath.txt

7. Without changing directories, redo the previous echo command, and this time redirect the output of the command (the relative pathname) into the file echopath.txt in your Base Directory (not in the current directory).

   Hint: For the redirection output file pathname, you must use a relative pathname that leads from your current directory Assignments down into the Base Directory. The relative pathname will contain one embedded slash separating two name components. The basename of the relative pathname must be the destination file name echopath.txt

8. Confirm that the Base Directory contains the new echopath.txt file.

Run the Checking Program to verify your work so far.

parent.txt

2. Without changing directories, use the echo command to save the relative pathname argument you just used, into file parent.txt in your Base Directory (not in the current directory).

   Hint: As you did above, redo the change directory command with the change directory command name replaced by echo so that the pathname argument echoes to the terminal screen. When that works, add redirection to redirect the screen output into the correct file in the Base Directory (not in the current directory).

   Hint: For the redirection output file pathname, you must use a relative pathname that leads from your current directory CST8207-16F down into the Base Directory. The relative pathname will contain two embedded slashes separating three name components. The basename of the relative pathname must be the destination file name parent.txt

3. Still in the current CST8207-16F directory, use the command from the worksheet to recursively walk the current directory and print all the pathnames under the current directory on your screen.

   Hint: You used this exact command to print all the pathnames under the current directory in Section 8 of Worksheet #02 HTML.

f0und.txt

4. Repeat the same recursive command you just used and redirect the output of the command into file f0und.txt in your Base Directory (not in your current directory). Note the strange spelling of the file name.

   Hint: For the redirection output file pathname, you must use a relative pathname that leads from your current directory CST8207-16F down into the Base Directory, as you did above. See the previous Hints.

5. Use a command that shows file names to confirm that the parent.txt and f0und.txt files are located only in the Base Directory and not in the current directory or anywhere else.

Run the Checking Program to verify your work so far.

newcal,txt

1. Copy the cal.txt file you created in Assignment #02 HTML into the Base Directory using the new name newcal,txt for the file. (Note carefully the punctuation character used in this name.)

1ldir

2. Create the following directory structure starting in the Base Directory and record (for study purposes) the series of commands you used to create it. Spelling and capitalization must be exactly as shown:
   1. Create the 1ldir directory in the Base Directory. Pay careful attention to the name; the first two characters of the name are not the same.
   2. Under directory 1ldir create two new directories named one and two (three letters each).
   3. Under directory one create new directory 0neOne (six characters, including one digit zero).
   4. Under directory two create new directory twOtwo (six letters, including one that is upper-case).

Hint: You can create the entire directory tree above using one single command with one option and two pathname arguments, as you did at the end of Section 4 in Worksheet #02 HTML. System administrators like to work efficiently – they learn how to do things quickly.

3. Check the structure of this directory tree using the same command as you used in the previous section. The correct directory tree under the Base Directory must look similar to the ASCII tree diagram below. The spelling and capitalization must be exactly as shown.

   1ldir
   |-- one
   |   `-- 0neOne
   `-- two
       `-- twOtwo

lIdir

4. Copy the directory 1ldir to new directory lIdir using the correct directory copy option, as you did in Section 3 of Worksheet #03 HTML. Pay careful attention to the new directory name; the first two characters of the name are not the same.

   Hint: lIdir must not exist before you do this copy! If it already exists, recursively remove it before you do the copy, or else you will get a spurious incorrect extra level of directory such as lIdir/1ldir

5. Check that the tree structure of lIdir is exactly the same as the tree structure of the 1ldir directory from which you copied it.

Run the Checking Program to verify your work so far.

mypaths.txt

2. When the five lines of recursive output above on your screen looks correct, redirect the output of the command into the file named mypaths.txt in the 0neOne directory that you created earlier under the lIdir directory.

   Hint: Draw a file system tree diagram so that you know what relative pathname to use. Don’t try to invent the pathname in your head!

   Hint: For the output redirection file, use a relative path from your current directory down into the 0neOne directory under lIdir. The relative pathname will contain three embedded slashes separating four name components. The basename of the relative pathname is the destination file name mypaths.txt

3. Make the 0neOne directory under lIdir your current directory. (Make sure you get the right one under lIdir and not 1ldir! Display your current working directory and make sure.)

   Hint: Draw a file system tree diagram so that you know what relative pathname to use. Don’t try to invent the pathname in your head!

4. Use a command to list the files in the current (0neOne) directory to confirm that the mypaths.txt file is here. Use another command to display the contents of the mypaths.txt file, and make sure it contains exactly five lines of pathnames from under the 1ldir directory.

mypaths.txt.copy

5. From in the 0neOne directory, copy the mypaths.txt file (from the current directory) into the twOtwo directory that is also under the lIdir directory, giving it the new name mypaths.txt.copy as the destination file name for the copy. Use relative pathnames to do the copy.

   Hint: Draw a file system hierarchy picture to help you derive the correct relative pathname. For the destination file, use a relative path from your current directory that goes up the tree and then down into the two directory. The relative pathname will contain four embedded slashes separating five name components. The basename of the relative pathname should be the destination file name.

copycmd.txt

6. Save a copy of the command line you just used into a file as follows:
   1. Use the Up-Arrow key to retrieve the copy command you just typed.
   2. Use the Left-Arrow key to move all the way left and then prefix the copy command line you just typed with the word echo; type the word echo followed by a space at the start of the command line, in front of the copy command name.
   3. Push the [Enter] key and confirm that the copy command name and its two relative pathname arguments echo onto the screen.
   4. Again use the Up-Arrow key to retrieve the echo command you just typed.
   5. To the right end of the echo command line, add redirection to redirect the echo output into file copycmd.txt in the Base Directory. No output should appear on screen.

   The copycmd.txt file should contain on one line: the copy command name followed by two relative pathname arguments, exactly as you typed it in the preceding question.

   Hints: Because the copycmd.txt output file must be located in the Base Directory, not in the current 0neOne directory, you need to specify a relative redirection output pathname that goes up several levels to the Base Directory. The relative pathname will contain three embedded slashes and many parent directories. The basename of the relative pathname is the destination file name copycmd.txt

   You will need to use the echo command to create another file later in this assignment. Remember how you used it here.

Run the Checking Program to verify your work so far.

mydir

• The command will create a directory named mydir in your Base Directory. The directory will contain some sub-directories and files.

• To know what files and directories have been created by the above command line, use a command that will recursively show all the files and directories under a starting directory. (You already used this command, above.) Make sure you use the correct command to recursively show all the files and directories, not just the first layer.

• You can re-execute the above create_mydir.sh command line to start this task over from scratch, if you make errors in this part of the assignment, but you will have to rename or remove the existing mydir first.

• You will be asked to make some changes to this existing set of files and directories. You must not make any changes other than the changes asked. If you accidentally create or delete files not required, you may change the modify time of sub-directories and you will have to erase the whole directory and start over.

All the following commands in this task section apply to files and directories under the new mydir directory. You will have to use commands to find some of the file names mentioned here; they may be located under sub-directories. (See Searching and Finding Files.) Some of these tasks may require more than one command to complete.

2. Find and read the file named README.txt (located somewhere under some directory under mydir). You have to find this file.

3. Read and then delete the file foo.txt that is in the same directory as the README.txt file. (Do not delete any other decoy files named foo.txt that may be in other directories.)

bar.bak

4. Move (rename) the file bar to be bar.bak (This is a move, not a copy. It renames the file.) Make sure you rename the file, not any decoy directories with the same name.

bar

5. Directly under the mydir directory, create a new empty directory named bar (three letters). (Make sure you create bar under mydir, not in your HOME or any other directory.)

movestuff

6. Find the file named stuff (not the directory with the same name) and move (rename) that stuff file to be named movestuff under the new directory bar that you just created. (This is a move/rename, not a copy.) Make sure you move the file, not any directory with the same name.

Run the Checking Program to verify your work so far.

btop1

1. Create the following directory structure starting in the Base Directory and record (for study purposes) the series of commands you used to create it. Spelling and capitalization must be exactly as shown:
   1. Create a directory named btop1 in your Base Directory.
   2. Under directory btop1 create two new directories named bdir1 and bdir2 (four letters and one digit each).
   3. Under directory bdir1 create new directory bdir1-1 (four letters, two digits, and one dash).
   4. Under directory bdir2 create new directory bdir2-1 (four letters, two digits, and one dash).

Hint: You can create the entire directory tree above using one single command with one option and two pathname arguments, as you did at the end of Section 4 in Worksheet #02 HTML. System administrators like to work efficiently – they learn how to do things quickly.

2. Verify that the directory tree under btop1 looks similar to the ASCII tree diagram below. The spelling and capitalization must be exactly as shown:

   btop1
   |-- bdir1
   |   `-- bdir1-1
   `-- bdir2
       `-- bdir2-1

3. Make the Base Directory your current directory and then use a command to recursively generate a list of all pathnames using btop1 as the starting directory.

   Hints: You used this recursive command many times in Section 8 of Worksheet #02 HTML. Do not use the tree or ls commands. The recursive output of all pathnames will be exactly five lines long and will contain this exact line in the output somewhere (along with another four lines):

   btop1/bdir2/bdir2-1

   Make sure the exact line above appears as one of the five lines! The word count of this command output must be: 5 5 70 and if the count is wrong, re-read all the words in ths step.

btop1find.txt

4. When the recursive output above on your screen looks correct, redirect the five lines of output of the command into the file named btop1find.txt in the Base Directory. (That file name has one digit in it.) The word count of this file must also be: 5 5 70.

5. RTFM in the Manual and find the single-letter option to the copy program that preserves mode, ownership, and timestamps when you copy. Make a note of this option in your own course notes; you will use it often as a system administrator.

btop2

6. Under your Base Directory create another directory btop2 that contains a copy of everything you created under btop1, with the timestamps preserved.

   Hint: The fastest way to do this is with a single recursive copy command, as you did in Section 3 of Worksheet #03 HTML, but add the option to preserve timestamps. Hint: Do not create the btop2 directory before you copy, or else you will get a spurious incorrect extra level of directory such as btop2/btop1

mt

7. Use a command to create an empty file named mt in each of the five directories from btop2 down. You will create five empty files, one in each of five directories. Hint: You can do this with one single command name and five relative pathnames. If you’re using the cd command to do this, you’re wasting time.

8. Make the btop2 directory your current directory and then use a command to recursively generate a list of all pathnames under your current directory. The recursive output of all pathnames under your current directory will be exactly ten lines long and will contain this exact line in the output somewhere (along with another nine lines):

   ./bdir2/bdir2-1/mt

   Make sure the exact line above appears as one of the ten lines! The word count of this command output must be: 10 10 115 and if the count is wrong, re-read all the words in this step.

btop2find.txt

9. When the recursive output above on your screen looks correct, redirect the ten lines of output of the command into the file named btop2find.txt in your Base Directory (not in the current directory). The word count of this file must also be: 10 10 115.

btop3

10. Under your Base Directory create another directory btop3 that contains a copy of everything that you created under btop2, with timestamps preserved. Hint: See the previous Hint!

mt3, mt2-1 etc.

11. Under btop3 rename each of the mt files to have the number of the immediate parent directory that contains it, e.g. rename btop3/mt to be btop3/mt3 and bdir2-1/mt to be bdir2-1/mt2-1, etc. You don’t know enough scripting yet to do this with a script; do each file manually.

    Hint: The -type f option to find may be useful here to generate a list of only file names and not show directory names.

12. Make the btop3 directory your current directory and then use a command to recursively generate a list of all pathnames under your current directory. The recursive output of all pathnames under your current directory will be exactly ten lines long and will contain this exact line in the output somewhere (along with another nine lines):

    ./bdir2/bdir2-1/mt2-1

    Make sure the exact line above appears as one of the ten lines! The word count of this command output must be: 10 10 124 and if the count is wrong, re-read all the words in this step.

btop3find.txt

13. When the recursive output above on your screen looks correct, redirect the ten lines of output of the command into the file named btop3find.txt in your Base Directory (not in the current directory). The word count of this file must also be: 10 10 124

Run the Checking Program to verify your work so far.

mymaze

1. Create a new directory named mymaze in your Base Directory.

2. Under the Source Directory there is a directory named maze (four letters) with many, many sub-directories and sub-sub-directories, etc. (The maze contains over 20,900 pathnames.) In this large maze, find the one file with a 12-character basename that looks similar to abcd0001-txt but where the eight-character abcd0001 part of the name is replaced by your own account userid.

   Hints:
   1. Review the definition of basename in the Pathnames class notes.
   2. Recall that you do not have permission to list the names of all the files in the Source Directory, but you can access the maze directory there because you know its name.
   3. This maze directory contains many hidden sub-directories; you need a special option to see hidden files and directories.
   4. Do not try to use cd or ls to find the file in the maze; the maze is very big. Use the correct command to recursively search the maze directory for the file name.
   5. You must use a single command that recursively finds files by basename to find your 12-character file name. You have previously seen the command you will need in the first item b. of Section 8 of Worksheet #02 HTML.
   6. Read the file when you find it. The file content will tell you clearly that you have found the right file. If you see XXX in the file, it is not the right file.
   7. Pay careful attention to the exact spelling of the 12-character basename of the required file.

mazepath.txt

3. When the above command has found your personal abcd0001-txt file in the maze and outputs exactly one line, put the absolute pathname of your personal file (one line) into a file named mazepath.txt in the mymaze directory that you created in step 1 above.

   Hint: It must be the absolute pathname. You will have to draw a file system diagram and figure out what that pathname is; no command will show it to you. You can test your absolute pathname by giving it as an argument to a command that reads pathnames, e.g. to ls, wc, cat, etc. and make sure you get no error message.

   Hint: You can use the echo command with output redirection to put one line of text into any file. (You used the echo comand in a similar way to create the one-line copycmd.txt file, earlier.) When you know the absolute pathname, give the echo command one argument that is the absolute pathname of your personal file in the maze. Make sure the pathname echoes onto your screen. Then, add output redirection to this echo command so that the echo output goes into the mazepath.txt file and not onto your screen. The mazepath.txt file should contain one line that is the absolute pathname of the found file in the maze.

treasure.txt

4. Copy only your one personal file from the maze into your mymaze directory using the new file name treasure.txt. Read the file to make sure it’s the right one before and after you copy it into your own mymaze directory; the file content will tell you clearly that you have found the right file. If you see XXX in the file, it is not the right file.

   Hint: Be careful not to copy the entire maze directory! Copy only the contents of one file into mymaze.

Run the Checking Program to verify your work so far.