I modified your code a bit: 

use warnings;
use strict;
use Fcntl;
my $SYSOPEN_MODE = O_WRONLY|O_CREAT;
if(exists $Fcntl::{'O_NONBLOCK'})
{
  print "Exists\n";
  $SYSOPEN_MODE |= &{ $Fcntl::{'O_NONBLOCK'} };
}

[download]
The output of this is really surprising to me: 
Exists
Your vendor has not defined Fcntl macro O_NONBLOCK, used at fctest.pl 
+line 8.

[download]
So 'exists' is not a good way to check for the existence of the macro; and it is not the exists expression which printed the error (we were mislead because the line number pointed to the 'if'; or did we just miscount the lines?).

-- 
Ronald Fischer <ynnor@mm.st>

In reply to Re: Fcntl constants missing by rovf
in thread Fcntl constants missing by nwetters

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