is there a /bin/sh method to tell the ending of a file

[John Levine]

>---------------------
>#!/bin/sh
>
>if [ ".gz" = "`echo \"$STRING\" | sed -n 's/.*\(\.gz\)$/\1/p'`" ]; then
> echo test;
>fi

Ewwww.  I think that we can now safely take advantage of
features added to the shell in the late 1970s.

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#!/bin/sh

case "$1" in
 *.gz) echo that is a gzipped file ;;
 *) echo that is not a gzipped file ;;
esac

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