From: Eric Hodel <drbrain@...7.net>
Date: 2011-02-10T08:55:15+09:00
Subject: Re: System calls with ` in parameters

On Feb 9, 2011, at 3:48 PM, Gerad S. wrote:

> Hi All,
> 
> I am trying to add functionality to an interesting script.  The part
> that is tripping me up is that I have to make a system call to echo, and
> feed several parameters.  One of the parameters occasionally includes
> the ` character.
> 
> Because of this, the syntax of:
> 
> `echo "#{someVar}" | ./some-script.py > "#{outputFile}"`
> 
> is breaking when #{someVar} contains the tick `.  This causes the
> command to fail because it executes up to the tick ` in someVar and not
> to the end as intended.
> 
> I have also tried using the system() command as follows:
> 
> system("echo \"#{someVar}\" | ./some-script.py > \"#{outputFile}\"")
> 
> But this fails when there is a tick ` in #{someVar} as well.
> 
> Any help would be appreciated.

Shellwords should do it:

ruby -rshellwords -e 'p Shellwords.escape "`"'