Perl error checking question


 
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# 1  
Old 09-10-2008
Perl error checking question

I am not very good with perl but trying to force myself to start learning...
I have a script that calls three other scripts in variables. I want to use a if statement to check the exit status and not sure how to do it..


This is basically what I have, the individual scripts print either a Y or N.
Code:
        $COMMAND1=`command1`;
        $COMMAND2=`command2`;
        $COMMAND3=`command3`;
        if ($COMMAND1 eq "N" || ($COMMAND2 eq "N" || ($COMMAND3 eq "N" ) {
                print "something here";
        } else {
                print "something else";
        }

This works, but I don't like it and it should be done with the exit status. I was reading up on this site....
Perl Special Variables

"$! When used in a numeric context, holds the current value of errno. If used in a string context, will hold the error string associated with errno.
$@ Holds the syntax error message, if any, from the last eval() function call."

I am just not sure how to implement it.
# 2  
Old 09-11-2008
By using backticks you are capturing the output of the shell command. This is not the same as its exit status.
For the exit status you need $? following your `STRING` (see perlop) or a system call (see perlfunc). Then the exit status is $?>>8 (read about $? in perlvar).
e.g.
Code:
$output=`command1`;
$status = $? >> 8;

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