blob: 65529a7020a794286cd8ed2ac9130e92e054ef2c (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
|
ans =
1.
-->exec('Example3.sci')
-->clear
-->flag=1
flag =
1.
-->mode(-1)
Current date is 23-Jun-2013
Welcome to the Textbook Companionship Project 2013
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Book Title : UNIX CONCEPTS AND APPLICATIONS
Book Edition : 4
Book Author : Sumitabha Das
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Code Author : Pranav Bhat T
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Chapter Number : 21
Chapter Title : Advanced Shell Programming
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Example 3 : Show the method of using eval in the shellscripts
****************************************************************
Answer :
INSTRUCTIONS :
1. Here all instructions are preloaded in the form of a demo
Initially the whole perl script is displaying and then
the result of the same can be seen in the command line interpreter.
2. PLEASE MAKE SURE THAT THE PERLSCRIPT INTERPRETER
EXISTS IN THE SYSTEM
OR THE COMMAND WOULD NOT WORK
3. PRESS ENTER AFTER EACH COMMAND to see its RESULT
4. PRESS ENTER AFTER EACH RESULT TO GO TO THE NEXT COMMAND
.............Press [ENTER] to continue..... UNIX SHELL SIMULATOR(DEMO VERSION WITH PRELOADED COMMANDS)
# Enter the name of the shellscript file whichever you desire
#!/bin/sh
# Script: dentry2.sh - Uses eval and shell functions
#
trap 'echo "Program interrupted";exit' HUP INT TERM
. mainfunc.sh # Invokes functions valid_string() and anymore ()
prompt1="Employee id : " ; prompt2="Name : "; prompt3="Designation : "
prompt4="Department : " ; prompt5="Date birth : ";prompt6="Basic pay : "
rekord=
flname=`valid_string "Enter the output filename: " 8`
while true ; do
while [ ${x:=1} -le 6 ] ; do # x first set to 1
eval echo \$prompt$x '\\c' 1>&2
read value$x
rekord="${rekord}`eval echo \\$value$x`|"
x=`expr $x + 1`
done
echo "$rekord"
anymore "More entries to add" 1&>2 || break
done > $flname
anymore() {
echo "\n$1 ?(y/n) : \c" 1>&2
read response
case "$response" in
y/Y) echo 1>&2 ; return 0 ;;
*) return 1 ;;
esac
}
# type the following command in the command line interpreter as soon as it appears
" h.sh "[ENTER]
$ h.sh #to execute the perlscript
---------------->Executing ShellScript in Command Line Prompt<--------------
$ exit #To exit the current simulation terminal and return to Scilab console
........# (hit [ENTER] for result)
BACK TO SCILAB CONSOLE...
Loading initial environment
-->diary(0)
|
