Php/docs/function.openlog
openlog
(PHP 4, PHP 5, PHP 7)
openlog — Open connection to system logger
说明
openlog
( string $ident
, int $option
, int $facility
) : bool
openlog() opens a connection to the system logger for a program.
The use of openlog() is optional. It
will automatically be called by syslog() if
necessary, in which case ident
will default
to false
.
参数
ident
The string
ident
is added to each message.option
The
option
argument is used to indicate what logging options will be used when generating a log message.openlog() Options Constant Description LOG_CONS
if there is an error while sending data to the system logger, write directly to the system console
LOG_NDELAY
open the connection to the logger immediately LOG_ODELAY
(default) delay opening the connection until the first message is logged
LOG_PERROR
print log message also to standard error LOG_PID
include PID with each message You can use one or more of these options. When using multiple options you need to
OR
them, i.e. to open the connection immediately, write to the console and include the PID in each message, you will use:LOG_CONS | LOG_NDELAY | LOG_PID
facility
The
facility
argument is used to specify what type of program is logging the message. This allows you to specify (in your machine's syslog configuration) how messages coming from different facilities will be handled.openlog() Facilities Constant Description LOG_AUTH
security/authorization messages (use LOG_AUTHPRIV
instead in systems where that constant is defined)LOG_AUTHPRIV
security/authorization messages (private) LOG_CRON
clock daemon (cron and at) LOG_DAEMON
other system daemons LOG_KERN
kernel messages LOG_LOCAL0
...LOG_LOCAL7
reserved for local use, these are not available in Windows LOG_LPR
line printer subsystem LOG_MAIL
mail subsystem LOG_NEWS
USENET news subsystem LOG_SYSLOG
messages generated internally by syslogd LOG_USER
generic user-level messages LOG_UUCP
UUCP subsystem Note:
LOG_USER
is the only valid log type under Windows operating systems
返回值
成功时返回 true
, 或者在失败时返回 false
。