How To Process System Exit Codes Using Perl Eval

Author: erics, March 9th, 2021

The trick to using eval to catch shell execution is to return twice, once inside the eval and once outside:

sub isMaintenance {
    my $return = eval {
        my $err=system("check_policy.sh | grep 'Policy is MAINTENANCE' >/dev/null 2>/dev/null");
        &debug("perl error code: $err");
        $err=$err / 256;
        &debug("system error code: $err");
        if ($err != 0) {
                # Not Maintenance
                if ($verbose) { warn "policy is NOT MAINTENANCE\n"; }
                return 0;
        } else { return 1; }
    };  
    return $return;
}

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sub isMaintenance {

my $return = eval {

my $err=system("check_policy.sh | grep 'Policy is MAINTENANCE' >/dev/null 2>/dev/null");

&debug("perl error code: $err");

$err=$err / 256;

&debug("system error code: $err");

if ($err != 0) {

# Not Maintenance

if ($verbose) { warn "policy is NOT MAINTENANCE\n"; }

return 0;

} else { return 1; }

};

return $return;

}

Neat!

Categories: How-To's, Technology Tags: Code, eval, Exit, Exit Code, howto, perl, Return, System | No comments

How To Escape Newlines In PHP For Javascript

Author: erics, January 11th, 2012

You must use all three lines together for it to work…YMMV:

$escaped = str_replace(chr(10),'\n',$original_value);
$escaped = str_replace(chr(13),'\r',$escaped);
$escaped = preg_replace("/(\r?\n)/","\n",$escaped);

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$escaped = str_replace(chr(10),'\n',$original_value);

$escaped = str_replace(chr(13),'\r',$escaped);

$escaped = preg_replace("/(\r?\n)/","\n",$escaped);

Categories: How-To's, Technology Tags: Backslash, break, carriage return, control-m, Escape, javascript, JS, line break, Newline, php, Return | No comments

How To Access Value Directly From A Hash Returned By A Perl Subroutine

Author: erics, May 5th, 2011

my $value = $self->myFunction()->{'result'};

Where:

sub myFunction {
   my $self=shift;
   
   ...code here...
   
   return {
          'status' => 0,
          'result' => 'Hello World',
   };
}

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my $value = $self->myFunction()->{'result'};

Where:

sub myFunction {

my $self=shift;

...code here...

return {

'status' => 0,

'result' => 'Hello World',

};

}

Categories: How-To's, Technology Tags: Hash, howto, perl, Return, Subroutine | No comments

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How To Process System Exit Codes Using Perl Eval

How To Escape Newlines In PHP For Javascript

How To Access Value Directly From A Hash Returned By A Perl Subroutine

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