How to parse config variables from external file to shell script

How do i use a config.txt to recursively pass a set of variables to a shell script

eg my config.txt looks like this :

[set_1]
path=c://dataset/set1
v1= a.bin
v2= b.bin

[set_2]
path=c://dataset/set2
v1= xy.bin
v2= abc.bin

[set_3]
..................

and so on .

and my testscript :

#!/bin/bash
.$1

echo $path $v1 $v2

Right now I am able to parse first set of variables . How do i move on to the subsequent set_2 , set_3 ...........

Thanks in advance
pradsh

You can do something like that :

# Function: get_config_list config_file
          # Purpose : Print the list of configs from config file
get_config_list()
{
   typeset config_file=$1

   awk -F '[][]' '
      NF==3 && $0 ~ /^\[.*\]/ { print $2 }
   ' ${config_file}
}

# Function : set_config_vars config_file config [var_prefix]
# Purpose  : Set variables (optionaly prefixed by var_prefix) from config in config file
set_config_vars()
{
   typeset config_file=$1
   typeset config=$2
   typeset var_prefix=$3
   typeset config_vars

   config_vars=$( 
        awk -F= -v Config="${config}" -v Prefix="${var_prefix}" '
        BEGIN { 
           Config = toupper(Config);
           patternConfig = "\\[" Config "]";
        }
        toupper($0)  ~ patternConfig,(/\[/ && toupper($0) !~ patternConfig)  { 
           if (/\[/ || NF <2) next;
           sub(/^[[:space:]]*/, "");
           sub(/[[:space:]]*=[[:space:]]/, "=");
           print Prefix $0;
        } ' ${config_file} )

   eval "${config_vars}"
}

#
# Set variables for all config from config file
#
file=config.txt
for cfg in $(get_config_list ${file})
do
   echo "--- Configuration [${cfg}] ---"
   unset $(set | awk -F= '/^cfg_/  { print $1 }') cfg_
   set_config_vars ${file} ${cfg} cfg_
   set | grep ^cfg_
done

Input file (config.txt)

[set_1]
path=c://dataset/set1
v1= a.bin
v2= b.bin

[set_2]
path=c://dataset/set2
v1= xy.bin
v2= abc.bin

[set_3]
v1 = value1

Output:

--- Configuration [set_1] ---
cfg_path=c://dataset/set1
cfg_v1=a.bin
cfg_v2=b.bin
--- Configuration [set_2] ---
cfg_path=c://dataset/set2
cfg_v1=xy.bin
cfg_v2=abc.bin
--- Configuration [set_3] ---
cfg_v1=value1

Since you aren't worried about accessing the First Set of Variables again, you can just source the second set... Using your example:

[set_1]
path=c://dataset/set1
v1= a.bin
v2= b.bin

[set_2]
path=c://dataset/set2
v1= xy.bin
v2= abc.bin

[set_3]
..................

and so on .

and my testscript :

#!/bin/bash
.$1 #Here you are sourcing set 1 - I assume

echo $path $v1 $v2 #here you are showing the variables

. $2 #Here you are sourcing set 2
echo $path $v1 $v2 #here you are showing the new variables

# Just make sure to call the script with the variable files as the first and second argument.