Shell Programming and Scripting

filename = charge.cfg
sectionname = [AUTORETRYTIMES]
networkid[1] = 1
retrytimes[1] = 2
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sectionname = [CHARGE]
networkid[2] = 1
retrytimes[2] = 2
filename = xyz.cfg
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#!/bin/bash
read -p "Section name: " SECTION
read -p "File name: " FILE
until [ "$L" = "filename = $FILE" ]; do read L; done # seek file name
until [ "$L" = "sectionname = [$SECTION]" ]; do read L; done # seek section name
IFS='='
while read A B
do
    [ "$VAR" = filename ] || [ "$VAR" = sectionname ] && break # if next file or section encountered
    eval "$A=${B:1}" # ${B:1} to cut the first char (space)
done < configuration.cfg

read
eval "$REPLY"

#!/bin/bash
while read A S B
do
    case $A in
        filename)    # process new file
            FILE=bin/$B
            unset SECT
            [ -f $FILE ] || { echo "$FILE not found"; unset FILE; }
        ;;
        sectionname) # new section
            [ -z "$FILE" ] && continue
            SECT="$B"
            # return the line number of section in $FILE
            N=$(grep -Fwn "$SECT" $FILE | cut -d':' -f1) || { echo "$SECT not found in $FILE "; unset SECT; }
        ;;
        *)    # process parameter
            if [ -n "$FILE" ] && [ -n "$SECT" ]
            then
                ((N++))
                sed -i "${N}i\n$A $S $B" $FILE
            fi
        ;;
    esac
done < configuration.cfg