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。
EXP_GLOB
(int)
Indicates that the pattern is a glob-style string pattern.
EXP_EXACT
(int)
Indicates that the pattern is an exact string.
EXP_REGEXP
(int)
Indicates that the pattern is a regexp-style string pattern.
EXP_EOF
(int)
Value, returned by expect_expectl(), when EOF is reached.
EXP_TIMEOUT
(int)
Value, returned by expect_expectl() upon timeout of seconds, specified in value of expect.timeout
EXP_FULLBUFFER
(int)
Value, returned by expect_expectl() if no pattern have been matched.