Uni/Syslog#

Interface to Unix syslog functionality.

Info

To use declarations from this page, include the <essence/uni/syslog.hpp> header.

The declarations are within the uni namespace.

enum class logopt : i32 #

Options used for the syslog.open() call.

enumerator none = 0#: No additional behaviour above default.

enumerator pid = LOG_PID#: Display the PID alongside the process identity in the log message, e.g.: <hostname> <program-name>[<PID>]: <message>.

enumerator console = LOG_CONS#: Log to the console if there are errors sending the message.

enumerator no_delay = LOG_NDELAY#: Don’t delay opening.

enumerator delay_open = LOG_ODELAY#

Delay open until first syslog() call (or uni::syslog.send()).

This is default behaviour.

enumerator no_wait = LOG_NOWAIT#: Don’t wait for console forks, DEPRECATED.

enumerator perror = LOG_PERROR#: Log to stderr as well.

enum class facility : i32 #

The various logging facility identifiers.

enumerator kernel = LOG_KERN#: Kernel messages.

enumerator user = LOG_USER#: Misc. user-level messages.

enumerator mail = LOG_MAIL#: Mail system messages.

enumerator news = LOG_NEWS#: Network news subsystem messages.

enumerator uucp = LOG_UUCP#: UUCP subsystem messages

enumerator daemon = LOG_DAEMON#: System daemon messages.

enumerator auth = LOG_AUTH#: Security and authorization messages.

enumerator cron = LOG_CRON#: Cron daemon messages.

enumerator printer = LOG_LPR#: Line printer subsystem messages.

enumerator local0 = LOG_LOCAL0#: Reserved for local use.

enumerator local1 = LOG_LOCAL1#: Reserved for local use.

enumerator local2 = LOG_LOCAL2#: Reserved for local use.

enumerator local3 = LOG_LOCAL3#: Reserved for local use.

enumerator local4 = LOG_LOCAL4#: Reserved for local use.

enumerator local5 = LOG_LOCAL5#: Reserved for local use.

enumerator local6 = LOG_LOCAL6#: Reserved for local use.

enumerator local7 = LOG_LOCAL7#: Reserved for local use.

enum class severity : i32 #

The various log severity levels, listed from highest severity level (emergency) to the lowest (debug).

enumerator emergency = LOG_EMERG#: System is unusable.

enumerator alert = LOG_ALERT#: Action must be taken immediately.

enumerator critical = LOG_CRIT#: Critical conditions.

enumerator warning = LOG_WARNING#: Warning conditions.

enumerator error = LOG_ERR#: Error conditions.

enumerator notice = LOG_NOTICE#: Normal but significant condition.

enumerator info = LOG_INFO#: Informational.

enumerator debug = LOG_DEBUG#: For debugging and tracing.

detail::syslog_t syslog#

The detail::syslog_t is an implementation detail, and all interaction is intended to go throught the global instantiation of the object.

Example

using namespace essence;

uni::syslog.open("program-name", uni::logopt::pid, uni::facility::user);
uni::syslog.send(uni::severity::info, "Hello from my program!");

// not strictly necessary, as the object closes the syslog on scope exit
uni::syslog.close();

class detail::syslog_t#

i32 mask(severity sv)#: Set the minimum severity to expose to the syslog. In practice, this means that any messages which are lesser than sv will be filtered out and not sent to the syslog.

void open(const char *ident, logopt opt, facility fac)#: Open the syslog for sending messages, with options opt and through the facility fac.

template<typename ...Args> void send(severity sv, std::string_view msg, Args&&... args)#: Send a message with severity sv to the syslog, with std::format arguments args applied.

void close()#: Close the syslog. Generally not needed, as the object closes the syslog on destruction.