Shell Programming and Scripting

[CODE]
eval $lgrep $SAM_CMD ; if [ $? -eq 0 ] ; then echo "No Error" ; fi
change to
eval $lgrep $SAM_CMD ; rslt=$? ; if [ "$rslt." = "0." ]; then echo "No Error"; fi

The original error message came from the extra semi-colon after "then".

Please post all relevant parts of the script, or the whole script.
Please post the command and the lines which set the variables.

It think I get your logic but I can't think of a simple grep which would return exit status zero when it doesn't find something. Obviously "grep -v" is irrelevant in this context.

Code:

eval $lgrep $SAM_CMD ; if [ $? -ne 0 ] ; then echo "No Error" ; fi

Btw. If this is commercial code it is rarely ever necessary or desirable to use "eval".
In portable Shell scripts I have seen commands like echo executed as ECHO where ECHO is a function which decides which syntax to use.

You can do the conditional test as follows

Code:

 [ "$?" -ne 0 ] && echo "No Error"

. I'm not sure what you're doing with the first part but this code here reads "Test exit status to be not equal to 0 and if that evaluates to true, echo 'No Error'. I prefer the conditional test like above as opposed to if statements. Keeps code cleaner imho.

&& says do this code if the code to the left is true. || says do this if it fails or is not true. Good for one liners instead of worrying about if then syntax. Hope that helps a little for the future :-)

DC Slick -

What is the complete command?

Code:

eval $lgrep $SAM_CMD ; if [ "$?" -ne 0 ] && echo "No Error"; fi

---------- Post updated at 12:13 PM ---------- Previous update was at 12:12 PM ----------

Aix Guy -

I tried running it, but it is giving me error message, even when the command has an output.

---------- Post updated at 12:14 PM ---------- Previous update was at 12:13 PM ----------

Methyl -

The condition has changed, i want an message when output is null.

Also, eval is because i am using pipe within variables.

Please expand the variables so I can see what is in them. It could be something in them that the parse is not getting right.

If you could tell us what $lgrep and $SAM_CMD represent that would help so much. Give us an example of what those variable values are. That's what aix-guy means by expand the variables. With the test [ "$?" -ne 0 ] && echo "No Error" you don't need the IF. So

Code:

 eval "$lgrep" "$SAM_CMD"; [ "$?" -ne 0 ] && echo "No Error"

is all you need.

Code:

Also, eval is because i am using pipe within variables.

Please post the whole script and sample command calls (if relevant). Perhaps there is a better way?