Concepts:

BASH shell (bash) programming
variables
arguments
control structures
Functions
test (for file types)
User Interaction

Description:

Create an executable BASH shell (bash) shell script that will:

• Require exactly 2 command line arguments and calls the error_function passing the error message that says You must enter Exactly 2 command line arguments, please try again: The error function takes the argument passed to it, prints it and then exits with an exit code of 1.
• Tell the user the values of the two command line arguments that they entered and ask for a Y or y or N or n to confirm that they did not make a typo. If they did do a typo, and the user enters an N or n meaning that they did make a mistake, then call the error function with a different message saying Program exiting because you said you had a typo, Please try again:.
• Tell the user if the command line arguments they entered were indeed files in the directory that the user specified. If one or both files did not exist, call the error function and give the message: Sorry, one or both files not located, please try again: .
  Then test to see if each file that exists is a regular type of file or if one or the other is a directory type of file. If one of the files is a directory type of file, call the error function and display this message: Sorry, one or both of the files that you entered was a directory, please try again:
• Tell the user if they own the files that they entered. (Hint: run man test to figure out how to test for these things.)
• Tell the user which file is newer of the 2 file names they entered.

Grading Structure:

• 50 points total Classroom sections will show me your program in class for a grade. Again make sure that the filename is: ~[username]/bin/[username]proj3.sh
• (15 pts) script named ~[yourusername]/bin/[yourusername]proj3.sh It must be executable by me but not be writable by me, it must also be on time..
• (10 pts) uses bash and correct syntax, and has no undesirable side effects.
• (25 pts) correct report information

Tools:
test, if-then-elif

1 #!/bin/bash
2
3 clear
4
5 error_fn()
6 {
7 echo "ERROR: $1"
8 exit 1
9 }
10
11 if [ $# -ne 2 ]
12 then
13 error_fn "You must enter Exactly 2 command line arguments, please try again:"
14 fi
15
16 echo the first argument was $1
17 echo the second argument was $2
18
19 if test $# -eq 2
20
21 echo -n "Are these the command line arguements you entered? Y or N":
22 read user_input
23
24 test $user_input = N
25 test $user_input = n
26 then
27 echo "Program exiting because you said you had a typo, Please try again: "
28 exit 0
29
30 fi
31
32 if test -f $1
33 then
34 echo "Yes $1 is a file in the current directory"
35 else
36 echo "Sorry, one or both files not located, please try again"
37 exit 0
38
39 fi
40
41 if test -f $2
42 then
43 echo "Yes $2 is a file in the current directory"
44 else
45 echo "Sorry, one or both files not located, please try again"
46 exit 0
47
48 fi
49 if
50 [ -d $1 ]
51 then
52 echo "Yes $1 is a file in the current directory"
53 else
54 echo "Sorry, one or both of the files you entered was a directory, please try again"
55 exit 0
56
57 fi
58
59 if [ -d $2 ]
60 then
61 echo "Yes $2 is a file in the current directory"
62 else
63 echo "Sorry, one or both of the files you entered was a directory, please try again"
64 exit 0
65
66 fi
67
68 if test -O $1
69 then
70 echo "Yes you are the owner of file $1"
71 else
72 echo "No, you are not the owner of file $1"
73 exit 0
74 fi
75
76 if test -O $2
77 then
78 echo "Yes, you are the owner of file $2"
79 else
80 echo "No, you are not the owner of file $2"
81 exit 0
82 fi

[shadowchaser@server1 ~]$ bash test3.sh dogs test

the first argument was dogs
the second argument was test
Are these the command line arguements you entered? Y or N:y
Yes dogs is a file in the current directory
Yes test is a file in the current directory
Sorry, one or both of the files you entered was a directory, please try again
[shadowchaser@server1 ~]$

[shadowchaser@server1 ~]$ ls -l
total 32
drwxr-xr-x 4 shadowchaser shadowchaser 4096 Jul 17 20:05 Desktop
-rw-rw-r-- 1 shadowchaser shadowchaser 13 Jul 4 09:13 dogs
-rw-rw-r-- 1 shadowchaser shadowchaser 83 Jul 19 19:22 ifthen.sh
-rwxr-xr-x 1 shadowchaser shadowchaser 1485 Jul 29 21:49 jcorzineproj3.sh
-rw-rw-r-- 1 shadowchaser shadowchaser 0 Jul 17 21:32 junk
-rw-rw-r-- 1 shadowchaser shadowchaser 234 Jul 19 19:18 test
-rw-rw-r-- 1 shadowchaser shadowchaser 59 Jul 30 08:30 test2.sh
-rw-rw-r-- 1 shadowchaser shadowchaser 1378 Jul 30 15:53 test3.sh
drwxrwxr-x 2 shadowchaser shadowchaser 4096 Jul 22 17:56 testing
[shadowchaser@server1 ~]$