module File_tail:sig
..end
File_replaced
occurs if the inode of the file changed and the file tail was
configured with ignore_inode_change = false
.module Error:sig
..end
module Warning:sig
..end
module Update:sig
..end
val create : ?read_buf_len:int ->
?read_delay:Core.Std.Time.Span.t ->
?retry_null_reads:bool ->
?break_on_lines:bool ->
?ignore_inode_change:bool ->
?start_at:[ `Beginning | `End | `Pos of Core.Std.Int64.t ] ->
?eof_latency_tolerance:Core.Std.Time.Span.t ->
?null_read_tolerance:Core.Std.Time.Span.t ->
string -> Update.t Import.Pipe.Reader.t
create file
creates a File_tail.t
that will immediately begin reading file
, and
then will start the stat-read loop.
read_buf_len
sets the size of the internal buffer used for making read system calls.
read_delay
sets how long the stat-read loop waits each time after it reaches eof
before stat'ing again. Setting read_delay
too low could cause unecessary load.
If retry_null_reads = true
, then reads that return data with null ('\000')
characters are ignored and cause the system to delay 0.2s and attempt the read again.
If retry_null_reads = false
, then the file tail will process data with nulls just as
it would any other data.
If break_on_lines = true
, the file tail will break data into lines on '\n'. If not,
the fill tail will return chunks of data from the end of the file as they are
available.
If ignore_inode_change = true
, the file tail will silently press on when the
file
's inode changes. If not, an inode change will cause the file tail to report an
error and stop. CIFS changes inodes of mounted files few times a day and we need
ignore_inode_change = true
option to keep tailers watching files on it alive.
start_at
determines the file position at which the file tail starts.
eof_latency_tolerance
affects the Did_not_reach_eof_for
warning.
null_read_tolerance
determines how long the tailing must observe null reads
before it will report a Delayed_due_to_null_reads_for
warning.