If I understood your situation correctly, I believe the solution is to use eval to pass the result of the command substitution though the shell's parser.
I'm using an old version of bash which does not support "set -A", so I'm using positional parameters instead of an array variable to try and explain myself. The principles involved are identical. Hopefully, I am able to get my point across
Code:
$cat eval.sh
# The goal is to assign the value of $first to $1
# and the value of $second to $2.
first='$second' second='boo far'
# 1)
# This first example exhibits the problem you are
# experiencing. The quotes intended to delimit the
# string are taken as part of the string itself,
# since command substitution occurs after the parsing
# step which cares about quoting.
set -- `echo \"$first\" \"$second\"`
echo "First positional parameter: $1"
echo "Second positional parameter: $2"
# Outputs:
# First positional parameter: "$second"
# Second positional parameter: "boo
# -----------------------------------------
# 2)
# Adding eval passes the result from command substitution
# through the parser, and the quotes are indeed interpreted
# as you'd like. However, with weak double quotes, if
# there is anything in the substituted text that would
# cause the shell to attempt parameter/command substitution,
# the output will be undesirably affected. In this case, the
# value of $first, the string "$second", is taken as a parameter
# which is then substituted, resulting in the value of $1
# being identical to that of $2.
eval set -- `echo \"$first\" \"$second\"`
echo "First positional parameter: $1"
echo "Second positional parameter: $2"
# Outputs:
# First positional parameter: boo far
# Second positional parameter: boo far
# -----------------------------------------
# 3)
# The correct solution is wrap the command substituted values
# in strong quotes, to ensure that they are taken literally and
# not word split when passed through the parser a second time.
eval set -- `echo \'$first\' \'$second\'`
echo "First positional parameter: $1"
echo "Second positional parameter: $2"
# Finally, the correct output:
# First positional parameter: $second
# Second positional parameter: boo far
Hope this helped,
alister
Last edited by alister; 01-04-2010 at 10:52 PM..
Reason: typos
Hi,
Please can someone help to return the array elements from a function. Currently the problem I face is that tempValue stores the value in myValue as a string while I need an array of values to be returned instead of string.
Many Thanks,
Sudhakar
the function called is:
... (5 Replies)
I would like to find a list of files in a directory less than 2 days old and put them into an array variable. And then search for each file in the array for a matching string say "Return-code= 0". If it matches, then display the array element with a message as "OK".
Your help will be greatly... (1 Reply)
Hi,
My doubt is how to access array elements..
Situation is as below:
#!/bin/ksh
set -x
typeset -i x=0
typeset -i y=0
typeset -i BID=0
typeset -i count=0
while ] ; do
x=`expr $x + 1`;
hwmgr show scsi > scsi.tmp
while read line; do
set... (1 Reply)
Is there a way to print multiple array elements without iterating through the array using bash?
Can you do something like...
echo ${array}and get all those separate elements from the array? (2 Replies)
Hi I have two arrays :
@arcb= (450,625,720,645);
@arca=(625,645);
I need to remove the elements of @arca from elements of @arcb so that the content of @arcb will be (450,720).
Can anyone sugget me how to perform this operation?
The code I have used is this :
my @arcb=... (3 Replies)
I have a script which takes backup of some configuration files on my server. It does that by using an array which contains the complete path to the files to backup.
It copys the files to a pre defined dir. Each "program" has it's own folder, ex. apache.conf is being copied to /predefined... (7 Replies)
Hi,
I can't find out how to create correct code to get multiplication of each elements of array. Let's say I enter array into command line (2 3 4 5 6 8) and i need output 2*3*4*5*6*8=5760.
I tried this one, but answer is 0.
for i in $@; do
mult=$((mult*i))done
echo "mult: " $mult
... (4 Replies)
Hi
I wanted to print random elements from an array at bash shell
I use the following code, but I always see first element getting printed
#!/bin/bash
c=1
expressions=(pink red white yellow purple)
while ]; do
echo "The value of RANDOM is $RANDOM"
selectedexpression=${expressions}]};... (5 Replies)
Hi All,
need help with reading the array and sum of the array elements.
given an array of integers of size N . You need to print the sum of the elements in the array, keeping in mind that some of those integers may be quite large.
Input Format
The first line of the input consists of an... (1 Reply)
I have an array code and output is below:
echo $1
while read -r fline; do
echo "%%%%%%$fline%%%%%"
fmy_array+=("$fline")
done <<< "$1"
Output:
CR30903 YU0007 SRIL CR30903 Yogesh SRIL
%%%%%%CR30903 YU0007 SRIL%%%%%
%%%%%%CR30903 Yogesh SRIL%%%%%
... (8 Replies)
Discussion started by: mohtashims
8 Replies
LEARN ABOUT OPENSOLARIS
shift
shift(1) User Commands shift(1)NAME
shift - shell built-in function to traverse either a shell's argument list or a list of field-separated words
SYNOPSIS
sh
shift [n]
csh
shift [variable]
ksh
*shift [n]
ksh
+shift [n]
DESCRIPTION
sh
The positional parameters from $n+1 ... are renamed $1 ... . If n is not specified, it is assumed to be 1.
csh
The components of argv, or variable, if supplied, are shifted to the left, discarding the first component. It is an error for the variable
not to be set or to have a null value.
ksh
The positional parameters from $n+1 $n+1 ... are renamed $1 ..., default n is 1. The parameter n can be any arithmetic expression that
evaluates to a non-negative number less than or equal to $#.
On this manual page, ksh(1) commands that are preceded by one or two * (asterisks) are treated specially in the following ways:
1. Variable assignment lists preceding the command remain in effect when the command completes.
2. I/O redirections are processed after variable assignments.
3. Errors cause a script that contains them to abort.
4. Words, following a command preceded by ** that are in the format of a variable assignment, are expanded with the same rules as a
variable assignment. This means that tilde substitution is performed after the = sign and word splitting and file name genera-
tion are not performed.
ksh93
shift is a shell special built-in that shifts the positional parameters to the left by the number of places defined by n, or 1 if n is
omitted. The number of positional parameters remaining is reduced by the number of places that are shifted.
If n is specified, it is evaluated as an arithmetic expression to determine the number of places to shift. It is an error to shift more
than the number of positional parameters or a negative number of places.
The following exit values are returned by shift in ksh93:
0 Successful completion. The positional parameters were successfully shifted.
>0 An error occurred.
On this manual page, ksh93(1) commands that are preceded by one or two + are treated specially in the following ways:
1. Variable assignment lists preceding the command remain in effect when the command completes.
2. I/O redirections are processed after variable assignments.
3. Errors cause a script that contains them to abort.
4. They are not valid function names.
5. Words, following a command preceded by ++ that are in the format of a variable assignment, are expanded with the same rules as a
variable assignment. This means that tilde substitution is performed after the = sign and field splitting and file name genera-
tion are not performed.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWcsu |
+-----------------------------+-----------------------------+
SEE ALSO csh(1), ksh(1), ksh93(1), sh(1), attributes(5)SunOS 5.11 20 Nov 2007 shift(1)
01-04-2010
