Shell Programming and Scripting

id1=we1;id2=er2;id3=rt3;id4=yu4

~redundant text not interested in ~
id1=1;id2=2;id3=4;
.................;id80=8

~redundant text not interested in ~
id1=1; ................;id9=11

list="id1,id2" #extract only id1 and id2, can be changed. each id is delimited by ','

#loop the list and extract the values of the id out
for i in $list
...
#store the value (eg 1 for id1) so that I can do a comparison 
#

#!/usr/bin/env bash

# command line args are: ["list"] data-file

list=" id1 id2 "                # default list: leading/trailing blanks are important
if [[ $# > 1 ]]                 # assume both list and filename supplied on command line
then
        list="$1"
        list=" ${list//,/ } "           # blank separate; lead/trail blanks important
        shift
fi

while read buf
do
        buf="id${buf#* id}"     # lop off leading garbage (assuming it does not contain ' id'
        buf="${buf//;/ }"       # ditch the semicolons
        for x in $buf
        do
                name=${x%%=*}           # split idx=y into name value pair
                value=${x#*=}
                if [[ $list == *" $name "* ]]   # its in the list if true
                then
                        eval $name=$value       # capture value
                fi
        done
done <$1

# you could print these as you capture them above, but if you need to do 
# other work before printing, etc., then this illustrates how you can dig them 
# out and print them later. 
for x in $list
do
        eval value=\$$x                 # suss out captured value
        
        if [[ ! -z $value ]]            # allow for cases where requested id was not in data (silently ignore)
        then
                if (( ${x#id} > 10 ))
                then
                        echo "$x=$value"
                else
                        echo $value
                fi
        fi
done

# ./justdoit
id1 has more value -> Printing Values.. " 1 1 "
Printing id2 Value = 2
Printing id3 Value = 4
Printing id4 Value = 1
Printing id5 Value = 2
Printing id6 Value = 4
Printing id7 Value = 1
Printing id8 Value = 21
id9 has more value -> Printing Values.. " 1 11 "
Printing id10 Value = 2
 
Printing id(s) and value(s) id11=4
Printing id(s) and value(s) id12=1
Printing id(s) and value(s) id13=2
Printing id(s) and value(s) id14=44
id15 value is nondefined
id16 value is nondefined
id17 value is nondefined
id18 value is nondefined
id19 value is nondefined

# cat infile
~redundant text not interested in ~
id1=1;id2=2;id3=4;id4=1;id5=2;id6=4;id7=1;id8=21;id9=1;id10=2;
id11=4;id12=1;id13=2;id14=44;
.................;id80=8
~redundant text not interested in ~
id1=1; ................;id9=11

 # justdoit
list="id1,id2,id3,id4,id5,id6,id7,id8,id9,id10,id11,id12,id13,id14,id15,id16,id17,id18,id19"
IFS=','
 for i in $list
  do
findit=`grep -o "$i=[0-9]*" infile | tr '\n' ' '`
   if [ `echo "$i" | sed 's/id//'` -lt 11 ] ; then
       if [ `echo "$findit" |tr -dc ' ' | wc -c` -gt 1 ] ; then
         echo $i has more value -> Printing Values.. \" `echo $findit | sed 's/id[0-9]*=//g'`\"
       else
     echo Printing $i Value = `grep -o "$i=[0-9]*" infile | sed 's/.*=//' `
       fi
   fi
        if [ "$i" = "id11" ] ; then
         echo ""
        fi
   if [ `echo $i | sed 's/id//'` -gt 10 ] ; then
     if [[ `grep -o "$i=[0-9]*" infile` == "" ]] ;then
         echo "$i value is nondefined"
          else
         echo "Printing id(s) and value(s) `grep -o "$i=[0-9]*" infile` "
     fi
   fi
  done