checking the return code

Shell Programming and Scripting
1

hi
i have a file, i am reading line by line and checking a line contains a string ,

`grep "Change state" $LINE`
if [ "$?" -eq 0 ]
then
echo "The line contains---"
else
echo "The line does not contains---"

i need to check the return code , but i am getting an error

please help

thanks
Satya

2

Don't use backticks, the redirection throws the output away:

grep "Change state" $LINE > /dev/null 2>&1
if [ "$?" -eq 0 ]
then
echo "The line contains---"
else
echo "The line does not contains---"
3

hi Franklin,
even if the line contains that string also it is not going into the if block,

pleae its urgent

4

Parameter of grep is filename not the line, you can give like

echo $LINE |grep -q "Change state"
if [ "$?" -eq 0 ]
then
echo "The line contains---"
else
echo "The line does not contains---"

5

The variable $LINE could be empty, try to echo the variable before the grep command.