Write Messages to the System Log

Write messages to the system log via the POSIX syslog interface. Since this is a thin wrapper around that interface, you may also want to take a look at its documentation. Note that neither open_syslog() nor close_syslog() is actually required, but using them is good practice.

Usage

open_syslog(
  identifier,
  open_immediately = FALSE,
  include_pid = FALSE,
  fallback_to_console = FALSE,
  echo = FALSE,
  facility = NULL
)

syslog(message, level = "INFO", facility = NULL)

close_syslog()

Arguments

identifier

A string identifying the application.

open_immediately

When TRUE, the connection will be opened immediately (equivalent to using LOG_NDELAY). Otherwise it will be opened when the first message is written to the log (equivalent to using LOG_ODELAY).

include_pid

When TRUE, include the process ID in the log message. Equivalent to using LOG_PID.

fallback_to_console

Write to the system console (e.g. /dev/console) if there is an error while sending to the system logger. Equivalent to using LOG_CONS.

echo

Also log the message to standard error. Equivalent to using LOG_PERROR. Note that this is not actually part of the POSIX specification, and may not be available on your platform. If that is the case, setting this to TRUE will generate a warning.

facility

The type of program doing the logging, according to the guidelines in RFC 5424. Generally one of "USER" or "LOCAL0" through "LOCAL7". When this is NULL, fall back on the default.

message

The message to write to the system log.

level

The priority level of the message. One of "DEBUG", "INFO", "NOTICE", "WARNING", "ERR", "CRITICAL", "ALERT", or "EMERGE" – in that order of priority. See RFC 5424 for the basis of this schema.

Examples

if (FALSE) { # \dontrun{
open_syslog("my_script")
syslog("Running script.", level = "INFO")
syslog("Possible issue.", level = "WARNING")
close_syslog()

# Opening the syslog is not strictly necessary. You can
# simply write a message and it will open the log with the
# process name (likely "R") as the default.

syslog("Hello from R!", level = "WARNING")
close_syslog()
} # }