UNIX for Dummies Questions & Answers

#!/bin/bash
x=5
while [$x -ge 0]
do
        echo $x
        x=`expr $x - 1`
        echo ""
done
echo ""

num_while.sh: line 5: [5: command not found

#!/bin/bash
x=5
while [ $x -ge 1 ]    # <-- space after [ and before ]
do
        echo $x
        x=`expr $x - 1`
        echo ""
done
echo ""

#!/bin/bash
x=5
while [ $x -ge 0 ]
do
        echo $x
        x=`expr $x - 1`
        echo ""
done
echo ""

#!/bin/bash
x=5
while [ $x -gt 0 ]
do
        echo $x
        x=`expr $x - 1`
        echo ""
done
echo ""