| 1234567891011121314151617 | #!/usr/bin/zshif [ $# -eq 0 ]; then    echo "Usage: $0 username@machine destination-port [local-port]"    exit 1fidestination=$1destinationport=$2if [ $# -eq 2 ]; then    localport=$destinationportelse    localport=$3fissh -q -N -L ${localport}:localhost:${destinationport} $destination
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