下列常量由此扩展定义，且仅在此扩展编译入 PHP 或在运行时动态载入时可用。
APC_ITER_ALL
(integer)
APC_ITER_ATIME
(integer)
APC_ITER_CTIME
(integer)
APC_ITER_DEVICE
(integer)
APC_ITER_DTIME
(integer)
APC_ITER_FILENAME
(integer)
APC_ITER_INODE
(integer)
APC_ITER_KEY
(integer)
APC_ITER_MD5
(integer)
APC_ITER_MEM_SIZE
(integer)
APC_ITER_MTIME
(integer)
APC_ITER_NONE
(integer)
APC_ITER_NUM_HITS
(integer)
APC_ITER_REFCOUNT
(integer)
APC_ITER_TTL
(integer)
APC_ITER_TYPE
(integer)
APC_ITER_VALUE
(integer)
APC_LIST_ACTIVE
(integer)
APC_LIST_DELETED
(integer)