View Source log_mf_h (stdlib v6.1.1)
An event handler that logs events to disk.
This module is a gen_event
handler module that can be installed in any
gen_event
process. It logs onto disk all events that are sent to an event
manager. Each event is written as a binary, which makes the logging very fast.
However, a tool such as the Report Browser (rb
) must be used to read the
files. The events are written to multiple files. When all files have been used,
the first one is reused and overwritten. The directory location, the number of
files, and the size of each file are configurable. The directory will include
one file called index
, and report files 1, 2, ...
.
See Also
Summary
Functions
Initiates the event handler. Returns Args
, which is to be used in a call to
gen_event:add_handler(EventMgr, log_mf_h, Args)
.
Types
-opaque args()
Term to be sent to gen_event:add_handler/3
.
-type b() :: non_neg_integer().
-type f() :: 1..255.
Functions
-spec init(Dir, MaxBytes, MaxFiles) -> Args when Dir :: file:filename(), MaxBytes :: non_neg_integer(), MaxFiles :: 1..255, Args :: args().
Equivalent to init(Dir, MaxBytes, MaxFiles, fun(_) -> true end)
.
-spec init(Dir, MaxBytes, MaxFiles, Pred) -> Args when Dir :: file:filename(), MaxBytes :: non_neg_integer(), MaxFiles :: 1..255, Pred :: fun((Event :: term()) -> boolean()), Args :: args().
Initiates the event handler. Returns Args
, which is to be used in a call to
gen_event:add_handler(EventMgr, log_mf_h, Args)
.
Dir
specifies which directory to use for the log files. MaxBytes
specifies
the size of each individual file. MaxFiles
specifies how many files are used.
Pred
is a predicate function used to filter the events. If no predicate
function is specified, all events are logged.