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Date: Sat, 8 Jul 2006 04:12:26 -0500
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Subject: Use of "empty character constant?"
From: php_lists@realplain.com ("Matt W")

Hi all,

I'm a C newbie and just started experimenting with the PHP internals a
couple weeks ago...  A few days ago I noticed assignment/comparison of char
variables to '' (nothing between single quotes) in, for example, the
is_numeric_string function (zend_operators.h), snprintf.c, spprintf.c, etc.
I don't understand what it's doing. :-/  The only references I can find are
about "empty character constant" compiler errors, which is what happens if I
try to use '' in the same way (VC++ Express).  Though PHP compiles fine with
these "constructs," so something must be special there?

Sorry to bother the list with this if it's a general C thing that should be
known and not PHP-code specific.  But I've tried to figure it out on my own
(which I have with other stuff so far :-)) and can't, so I'd appreciate it
if someone can clue me in!


Thanks,
Matt