Usted buscó: undefined (Coreano - Inglés)

undefined
tired

constants may not be redefined or undefined once they have been set; and
the default behaviour is case-sensitive; i.e.

8. when linking php, it complains about a number of undefined references.
if it does, you should really upgrade to a recent version of gnu make.

calculate (base raised into power exp) modulo mod. if exp is negative, result is undefined.
if exp is negative, result is undefined.

8. some operating systems: i have installed php without errors, but when i try to start apache i get undefined symbol errors:
this has actually nothing to do with php, but with the mysql client libraries.

all registered variables are serialized after the request finishes. registered variables which are undefined are marked as being not defined. on subsequent accesses, these are not defined by the session module unless the user defines them later.
it might be more appropiate to use a shared memory based filesystem (such as tmpfs on solaris / linux, or / dev / md on bsd) to store sessions in files, because they are properly locked.

cgi.force_redirect is necessary to provide security running php as a cgi under most web servers. left undefined, php turns this on by default. you can turn it off at your own risk.
you can turn it off at your own risk.

call_user_function() returns success on success, and failure in case the function cannot be found. you should check that return value! if it returns success, you are responsible for destroying the retval pval yourself (or return it as the return value of your function). if it returns failure, the value of retval is undefined, and you mustn't touch it.
if it returns failure, the value of retval is undefined, and you mustn 't touch it.