Portability	Posix
Stability	provisional
Maintainer	simons@cryp.to

System.Posix.Syslog

Contents

Marshaled Data Types
Haskell API to syslog
Helpers
Low-level C functions

Description

FFI bindings to Unix's syslog(3). Process this file with hsc2hs to obtain a Haskell module.

Synopsis

Marshaled Data Types

data Priority Source

Log messages are prioritized.

Constructors

Emergency	system is unusable
Alert	action must be taken immediately
Critical	critical conditions
Error	error conditions
Warning	warning conditions
Notice	normal but significant condition
Info	informational
Debug	debug-level messages

Instances

Bounded Priority
Enum Priority
Eq Priority
Show Priority

data Facility Source

Syslog distinguishes various system facilities. Most applications should log in USER.

Constructors

KERN	kernel messages
USER	user-level messages (default unless set otherwise)
MAIL	mail system
DAEMON	system daemons
AUTH	security/authorization messages
SYSLOG	messages generated internally by syslogd
LPR	line printer subsystem
NEWS	network news subsystem
UUCP	UUCP subsystem
CRON	clock daemon
AUTHPRIV	security/authorization messages (effectively equals `AUTH` on some systems)
FTP	ftp daemon (effectively equals `DAEMON` on some systems)
LOCAL0	reserved for local use
LOCAL1	reserved for local use
LOCAL2	reserved for local use
LOCAL3	reserved for local use
LOCAL4	reserved for local use
LOCAL5	reserved for local use
LOCAL6	reserved for local use
LOCAL7	reserved for local use

Instances

Bounded Facility
Enum Facility
Eq Facility
Show Facility

data Option Source

Options for the syslog service. Set with withSyslog.

Constructors

PID	log the pid with each message
CONS	log on the console if errors in sending
ODELAY	delay open until first `syslog()` (default)
NDELAY	don't delay open
NOWAIT	don't wait for console forks: DEPRECATED
PERROR	log to `stderr` as well (might be a no-op on some systems)

Instances

Bounded Option
Enum Option
Eq Option
Show Option

Haskell API to syslog

withSyslog :: String -> [Option] -> Facility -> IO a -> IO aSource

Bracket an IO computation between calls to _openlog and _closelog. Since these settings are for the process, multiple calls to this function will, unfortunately, overwrite each other.

Example:

 main = withSyslog "my-ident" [PID, PERROR] USER $ do
          putStrLn "huhu"
          syslog Debug "huhu"

syslog :: Priority -> String -> IO ()Source

Log a message with the given priority.

Helpers

useSyslog :: String -> IO a -> IO aSource

useSyslog ident = withSyslog ident [PID, PERROR] USER

safeMsg :: String -> String Source

Escape any occurances of '%' in a string, so that it is safe to pass it to _syslog. The syslog wrapper does this automatically.

Low-level C functions

_closelog :: IO ()Source

_openlog :: CString -> CInt -> CInt -> IO ()Source

_setlogmask :: CInt -> IO CInt Source

_syslog :: CInt -> CString -> IO ()Source