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# 8  
Old 06-27-2013
Please always state your problem clearly. By changing the requirement you are simply wasting the time of the member who tried to help you.

I would suggest using Associative Arrays for this requirement:
Code:
#!/bin/bash

typeset -A arr

while read line
do
        var="${line%%=*}"
        for key in ${line//,/ }
        do
                val="${key#${var}=}"
                val="${val%=*}"
                if [ ! -z arr["$var"] ]
                then
                        arr["$var"]="${arr["$var"]} $val"
                else
                        arr["$var"]="$val"
                fi
        done
done < file

for k in "${!arr[@]}"
do
        printf "%s %s\n" "$k" "${arr["$k"]}"
done

Input:
Code:
$ cat file
temp=/usr=25,/usr/lib=12
bin=12
etc=45
lib=12:6

Output:
Code:
$ ./script.bash
bin  12
etc  45
lib  12:6
temp  /usr /usr/lib

# 9  
Old 06-28-2013
Hi,

Not able to get the output properly.


Code:
#!/bin/bash

typeset -a arr

while read line
do
        var="${line%%=*}"
        for key in ${line//,/ }
        do
                val="${key#${var}=}"
                val="${val%=*}"
                if [ ! -z arr["$var"] ]
                then
                        arr["$var"]="${arr["$var"]} $val"
                else
                        arr["$var"]="$val"
                fi
        done
done < file

for k in "${!arr[@]}"
do
        printf "%s %s\n" "$k" "${arr["$k"]}"
done

file:
Code:
temp=/usr=25,/usr/lib=12
bin=12
etc=45
lib=12:6

output:
Code:
# sh readfile.sh
0  /usr /usr/lib 12 45 12:6


Can we write the code in multilple function like below and need to use "eval" command to get the parameter name and respective value from the main function.
Overall I have to get the correct output for the below code.
Code:
#! /bin/sh
typeset -a arr

read_params()
{
#while read line
until [ -z "$1" ]
do
    if [ `expr index "$1" =` != 0 ] ; then
        var="${1%%=*}"
        for key in ${1//,/ }
        do
                val="${key#${var}=}"
                val="${val%=*}"
                if [ ! -z arr["$var"] ]
                then
                        arr["$var"]="${arr["$var"]} $val"
                else
                        arr["$var"]="$val"
                fi
        done
            eval $var=\"${arr["$var"]}\"
    fi
shift
done
#done < $1

for k in "${!arr[@]}"
do
        printf "%s %s\n" "$k" "${arr["$k"]}"
done

}

main()
{
read_params `cat file`

echo "$temp  and $lib"

}

main

Expected output:
Code:
# sh readfile.sh
/usr /usr/lib and 12:6

Please let me know what would be the mistake I did in the above code.
Last edited by munna_dude; 06-28-2013 at 05:03 AM..
# 10  
Old 06-28-2013
I said associative arrays not indexed arrays:
Code:
typeset -A arr

# 11  
Old 06-28-2013
Quote:
Originally Posted by Yoda
I said associative arrays not indexed arrays:
Code:
typeset -A arr


Correct but the below error caused to modified it as "-a".

Quote:
# typeset -A
-bash: typeset: -A: invalid option
typeset: usage: typeset [-afFirtx] [-p] name[=value] ...
# 12  
Old 06-28-2013
This feature is available only on certain systems.

I tested this code on below system and version and it works:
Code:
$ bash --version
GNU bash, version 3.2.25(1)-release (x86_64-redhat-linux-gnu)
Copyright (C) 2005 Free Software Foundation, Inc.

But it will not work on below system and version:
Code:
$ bash --version
GNU bash, version 3.2.51(1)-release (sparc-sun-solaris2.10)
Copyright (C) 2007 Free Software Foundation, Inc.

# 13  
Old 06-28-2013
Bash 3 does not have associative arrays. That is a bash 4 feature. If it happens to work in a particular version of bash 3 it probably is an undocumented feature and should not be relied upon.

As an alternative one could use ksh93 instead, which is a fast and advanced shell that also knows associative arrays.
# 14  
Old 07-03-2013
Quote:
Originally Posted by munna_dude
Hi,

Not able to get the output properly.


Code:
#!/bin/bash

typeset -a arr

while read line
do
        var="${line%%=*}"
        for key in ${line//,/ }
        do
                val="${key#${var}=}"
                val="${val%=*}"
                if [ ! -z arr["$var"] ]
                then
                        arr["$var"]="${arr["$var"]} $val"
                else
                        arr["$var"]="$val"
                fi
        done
done < file

for k in "${!arr[@]}"
do
        printf "%s %s\n" "$k" "${arr["$k"]}"
done

file:
Code:
temp=/usr=25,/usr/lib=12
bin=12
etc=45
lib=12:6

output:
Code:
# sh readfile.sh
0  /usr /usr/lib 12 45 12:6


Can we write the code in multilple function like below and need to use "eval" command to get the parameter name and respective value from the main function.
Overall I have to get the correct output for the below code.
Code:
#! /bin/sh
typeset -a arr

read_params()
{
#while read line
until [ -z "$1" ]
do
    if [ `expr index "$1" =` != 0 ] ; then
        var="${1%%=*}"
        for key in ${1//,/ }
        do
                val="${key#${var}=}"
                val="${val%=*}"
                if [ ! -z arr["$var"] ]
                then
                        arr["$var"]="${arr["$var"]} $val"
                else
                        arr["$var"]="$val"
                fi
        done
            eval $var=\"${arr["$var"]}\"
    fi
shift
done
#done < $1

for k in "${!arr[@]}"
do
        printf "%s %s\n" "$k" "${arr["$k"]}"
done

}

main()
{
read_params `cat file`

echo "$temp  and $lib"

}

main

Expected output:
Code:
# sh readfile.sh
/usr /usr/lib and 12:6

Please let me know what would be the mistake I did in the above code.

Hi,

Observed a strange behavior from the above code.

Code:
arr["$var"]="${arr["$var"]} $val"

above snippet will have the space in front of the text.
It requires if the string having two variable(Ex: temp=/usr=25,/usr/lib=12) but it is not required when the string contains only a variable(Ex: etc=45).



value=/bin/$etc
resulting value="/bin/ 45" it should be value="/bin/45".

The space has to avoid when we do "eval"
eval $var=\"${arr["$var"]}\"

Is this possible, please let me know the way.
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