Shell Programming and Scripting

run1.txt "testing1"
run2.txt "testing2"

run1.txt "testing1"
run2.txt "testing1"

!/bin/bash

run_number=0

((run_number++)) #run_number is now 1

run="testing$run_number" #run is now 'testing1'

echo $run_number #displays 1

cp template.txt run1.txt #make a copy of a file that contains "hello"

sed -i 's#hello#'$run'#g' run1.txt #replace "hello" with var run ("testing1")

cat run1.txt #display new contents of file, "testing1"

echo "--------------------------------------------"

((run_number++)) #increment variable so that now, run_number=2

echo $run_number #displays 2

cp template.txt run2.txt #make copy of file that contains "hello"

sed -i 's#hello#'$run'#g' run2.txt #replace "hello" with "testing2"

cat run2.txt #display "testing2"?? this returns testing1

run="testing$run_number" #run is now 'testing1

run="testing$run_number"

#!/bin/bash

number=1
string="Testing"

var=$string$number
echo "number: $number"
echo "string: $string"
echo "var: $var"
echo "---"

number=2
echo "number: $number"
echo "string: $string"
echo "var: $var"
echo "---"

var=$string$number
echo "number: $number"
echo "string: $string"
echo "var: $var"
echo "---"

$ ./script.sh 
number: 1
string: Testing
var: Testing1
---
number: 2
string: Testing
var: Testing1
---
number: 2
string: Testing
var: Testing2
---
$

((run_number++))
run=running$run_number
# or
run=running$((++run_number))

#!/bin/bash
for ((run_number=1; run_number<=2; run_number++))
do
  run=testing$run_number
  runfile=run${run_number}.txt
  cp "template.txt" "$runfile"
  echo "$run_number"
  sed -i "s#hello#${run}#g" "$runfile" #replace "hello" with var run
  cat "$runfile" #display new contents of file 
  echo "--------------------------------------------"
done

 
container='abc${myvar}xyz'
myvar=4711
actual_value=$(eval "echo $container")

container()
{
   echo "abc${myvar}xyz"
}
myvar=4711
actual_value=$(container)