README
¶
tail
Tail a file programmatically just like you run shell command tail -f /somefile.
Features
- support tail a non-exist file until that file exists
- tail works even if file get removed or truncated
- tail from specified offset
Basic usage
// closeFunc is used to stop tailing
lineCh, closeFunc, errCh := tail.TailF("/path/to/file", true)
go func() {
for {
select {
case <-errCh:
return
case line := <-lineCh:
fmt.Println(line)
}
}
}()
Advance usage
by default, tail poll file delete/truncate-event every 10 seconds, you can config poll interval to satisfy your own needs.
lineCh, closeFunc, errCh := tail.TailWithConfig("/path/to/file", true, &tail.Config{PollInterval: 500 * time.Millisecond})
go func() {
for {
select {
case <-errCh:
return
case line := <-lineCh:
fmt.Println(line)
}
}
}()
More configs
config tail offset
// tail.SeekFromStart/tail.SeekFromEnd/tail.SeekOffsetAuto
lineCh, closeFunc, errCh := tail.TailWithConfig("/path/to/file", true, &tail.Config{
PollInterval: 500 * time.Millisecond,
Offset: tail.SeekFromStart,
})
Limitations
Not tested on windows.
Documentation
¶
Index ¶
Constants ¶
View Source
const ( // file is eof, eof might triggered multiple times. EventEof = "eof" // if the tailing file get truncated or deleted, tail will restart EventTailRestart = "rs" )
Variables ¶
View Source
var ( //SeekFromEnd tail file from end SeekFromEnd = &SeekOffset{ Offset: 0, Whence: io.SeekEnd, } // SeekOffsetAuto tail file from offset (end - 1000) if file size is gt than 1000, else tail from start SeekOffsetAuto = &SeekOffset{ Offset: 0, Whence: -1, } // SeekFromStart tail file from offset 0 SeekFromStart = &SeekOffset{ Offset: 0, Whence: io.SeekStart, } )
Functions ¶
Types ¶
type Config ¶
type Config struct {
PollInterval time.Duration
Offset *SeekOffset
Follow bool
}
func NewDefaultConfig ¶
func NewDefaultConfig() *Config
type SeekOffset ¶
Source Files
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