Is there any reason that you are writing a shell script rather than making it a pure perl script in the first place?

Assuming there is, using double quotes to allow shell interpretation (as suggested by the pusher robot) is one way to do it, but it could get messy if you find yourself wanting both shell and perl variables.

You could set the variables directly in the perl rather than use shell variables in the first place.

Or, you could write your perl one-liner to read them off the command line.

perl -spe 's/mymodel/$model/' -- -model=1200 mytext.txt
[download]

perl -spe 's/mymodel/$arg/' -- -arg=$model mytext.txt
[download]

-sauoq
"My two cents aren't worth a dime.";

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We are the carpenters and bricklayers of the Information Age.

Don't go borrowing trouble. For programmers, this means Worry only about what you need to implement.

Please remember that I'm crufty and crochety. All opinions are purely mine and all code is untested, unless otherwise specified.

Or replace the single quotes with double quotes (so the shell can do var substitution).

That won't work. His $model is a shell variable, not an environment variable. (It hasn't been exported.)

-sauoq
"My two cents aren't worth a dime.";