Shell Programming and Scripting

Hello All,

I have a whole bunch of shell scripts written in a ksh environment and which successfully execute there. However, I found out that they eventually need to be used in a sh environment. So some commands like some_variable=$(some_command) fail because sh doesn't understand $(.....). I identified a list of scripts that have the $(.....) statements. Now I have to replace all those with `.....`

There must be someway I can automate this find and replace action right? Can you please point me in the right direction? Can I use sed for it? If so, what is the exact command? I can identify the statements using the regex '\$(.*)' but I don't know how to replace the command with `...`
I guess I have to parse each line of each file in a loop and do the substitution but I don't know the substituion command.
Thanks in advance for ur help.

Or can you acquire/compile ksh for that environment?

thanks for ur response. unforunately, i am not in a position to change the ksh environment to sh although that would be wise to do .

What will the deployed OS be? It may be that there is a POSIX shell in that environment that will handle most or this syntax, reducing the amount of changes you will need to do.

reborg, I'm just a shell programmer and the OS is solaris (which I access using putty from windows). Both sh and ksh seem to be installed (I can execute both from prompt). Should I use a C solution (pressed for time)? Thanks in advance.

Then why not use "ksh" if you have it?

To me it is madness to have working scripts, that then you have to rewrite just to use a different shell when they can be called as child processes by shell scripts of any other flavour.

If time is pressing why make what sound like tens or hundreds of changes that then require regression testing? It sounds like you are basically taking working production scripts and turning them into development projects.

So, you do the simple changes, then what about array variables and all the other ksh features?

Your trust and faith in these new scripts should be at rock bottom until they are fully tested, not exactly the thing to do if you are pressed for time.

wise counsel, porter. Thanks.

However, the scripts are for the 'production system' which apparently does not have ksh, while the development system does (Don't ask me why). That is why I am scrambling to convert them here. Most should be simple in that they don't use arrays. Only thing that I can think of is the issue with $(...) commands. Any other issue should be caught by the testing people - not expecting too many though. I had this shell differences thing in the back of my mind when I made the scripts but I guess I was not wary enough/ didn't have enough information about the differences.