expr syntax error

baosheng

Hi guys.I wrote a shell script.But it doesn't work well.Can you help me?
The script is

#!/bin/sh
echo "please input a file name"
read file_name
date
num=1
while [ $num -lt 10 ]
do
gzip $file_name
gzip -d *.gz
num=`expr $num +1`
done
date

and this is the executing result
[root@myENIAC program]# sh deflate_time.sh
please input a file name
xlxfg512.txt
Mon Jun 6 15:30:55 CST 2005
expr: syntax error
deflate_time.sh: line 6: [: -lt: unary operator expected
Mon Jun 6 15:30:55 CST 2005

huhuegg

Post by baosheng

num=`expr $num +1`

应该是：
num=`expr $num + 1`