Copy protection of a korn-shell script

rgustavs used Ask the Experts™
We have developed a korn shell script that we would like copy protect the source code. What kind of options do we have? The script is quite lenghy and it is not a preferred solution to rewrite it into a compiled language.

This is urgent for us.

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Don't think you can!
Unless you did something like:
encrypt the script
create a small wrapper program, which would be compiled, that un-encrypts the script, and runs it.
However I'm not sure that this would prevent someone ploughing through truss outputs to read the script.


I got an answer from another source proposing that I'll use sc-bind from It is a c-program that implements the logic that liddler proposes. I have aslo got suggestions to use


I'll get back with comments on sc-bind. We are testing it now.

Are you selling this script?

If you will use that inside your company, then you could use only chmod command to change permission
Top Expert 2007

Depends on what level of "protection" you require.  I think a good chunk of the Perl FAQ is particularly relevant here:

  How can I hide the source for my Perl program?
            Delete it. :-) Seriously, there are a number of (mostly
            unsatisfactory) solutions with varying levels of ``security''.

            First of all, however, you *can't* take away read permission,
            because the source code has to be readable in order to be
            compiled and interpreted. (That doesn't mean that a CGI script's
            source is readable by people on the web, though--only by people
            with access to the filesystem.) So you have to leave the
            permissions at the socially friendly 0755 level.

            Some people regard this as a security problem. If your program
            does insecure things and relies on people not knowing how to
            exploit those insecurities, it is not secure. It is often
            possible for someone to determine the insecure things and
            exploit them without viewing the source. Security through
            obscurity, the name for hiding your bugs instead of fixing them,
            is little security indeed.

            You can try using encryption via source filters (Starting from
            Perl 5.8 the Filter::Simple and Filter::Util::Call modules are
            included in the standard distribution), but any decent
            programmer will be able to decrypt it. You can try using the
            byte code compiler and interpreter described below, but the
            curious might still be able to de-compile it. You can try using
            the native-code compiler described below, but crackers might be
            able to disassemble it. These pose varying degrees of difficulty
            to people wanting to get at your code, but none can definitively
            conceal it (true of every language, not just Perl).

            It is very easy to recover the source of Perl programs. You
            simply feed the program to the perl interpreter and use the
            modules in the B:: hierarchy. The B::Deparse module should be
            able to defeat most attempts to hide source. Again, this is not
            unique to Perl.

            If you're concerned about people profiting from your code, then
            the bottom line is that nothing but a restrictive license will
            give you legal security. License your software and pepper it
            with threatening statements like ``This is unpublished
            proprietary software of XYZ Corp. Your access to it does not
            give you permission to use it blah blah blah.'' We are not
            lawyers, of course, so you should see a lawyer if you want to be
            sure your license's wording will stand up in court.
Here is a shell script compiler, It might be handy and also it is  Free. 

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