How to create incrementing counter

Shell Programming and Scripting
1

i am using SCO OpenServer 5

I wan to use bash and have a incrementing counter.
e.g.

#!/bin/bash

counter=1

let "counter+=1"

echo $counter

It says that it does not recognise let
So how should i do it?

2

#!/bin/bash
counter=1
counter=`expr $counter + 1`
echo $counter

3

nope, does not work
result

1+1
4

> cat counter.bash
#!/bin/bash
counter=1
counter=`expr $counter + 1`
echo $counter

> bash counter.bash
2

5

Works for me, did you copy + paste it correctly?

Actually your original script works here, too; maybe you have a really old bash. The expr script should work regardless, though.

6

let is a built-in command, when we run it in script, it does not working. we can say subshell.

What can we do to run it in subshell.

  • nilesh