You could also create environment variables that the shell will be happy to interpolate for you. 

$ perl -e'$ENV{host}="localhost"; system $ARGV[0]' 'echo $host'
localhost

[download]
The above is basically the same as 
$ host=localhost sh -c 'echo $host'
localhost

[download]

In reply to Re: Command Line Arg contains Variable and more (pass the buck) by ikegami
in thread Command Line Arg contains Variable and more by VinsWorldcom

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