Delete seek_offset, seek_whence and follow configs for tail input plugin

docs/DATA_FORMATS_INPUT.md

@@ -330,12 +330,6 @@ For details, please see the comments in the following configuration example.
   ##
   filename = "/var/log/nginx/access.ltsv.log"
 
-  ## Seek to this location before tailing
-  seek_offset = 0
-
-  ## Seek from whence. See https://golang.org/pkg/os/#File.Seek
-  seek_whence = 0
-
   ## Reopen recreated files (tail -F)
   re_open = true
 
@@ -348,9 +342,6 @@ For details, please see the comments in the following configuration example.
   ## Set this to true if the file is a named pipe (mkfifo)
   pipe = false
 
-  ## Continue looking for new lines (tail -f)
-  follow = true
-
   ## If non-zero, split longer lines into multiple lines
   max_line_size = 0
 

plugins/inputs/tail/README.md

@@ -32,12 +32,6 @@ It works like the BSD `tail` command and can keep reading when more logs are add
   ##
   filename = "/var/log/nginx/access.ltsv.log"
 
-  ## Seek to this location before tailing
-  seek_offset = 0
-
-  ## Seek from whence. See https://golang.org/pkg/os/#File.Seek
-  seek_whence = 0
-
   ## Reopen recreated files (tail -F)
   re_open = true
 
@@ -50,9 +44,6 @@ It works like the BSD `tail` command and can keep reading when more logs are add
   ## Set this to true if the file is a named pipe (mkfifo)
   pipe = false
 
-  ## Continue looking for new lines (tail -f)
-  follow = true
-
   ## If non-zero, split longer lines into multiple lines
   max_line_size = 0
 

plugins/inputs/tail/tail.go

@@ -34,12 +34,6 @@ const sampleConfig = `
   ##
   filename = "/var/log/nginx/access.ltsv.log"
 
-  ## Seek to this location before tailing
-  seek_offset = 0
-
-  ## Seek from whence. See https://golang.org/pkg/os/#File.Seek
-  seek_whence = 0
-
   ## Reopen recreated files (tail -F)
   re_open = true
 
@@ -52,9 +46,6 @@ const sampleConfig = `
   ## Set this to true if the file is a named pipe (mkfifo)
   pipe = false
 
-  ## Continue looking for new lines (tail -f)
-  follow = true
-
   ## If non-zero, split longer lines into multiple lines
   max_line_size = 0
 
@@ -134,16 +125,12 @@ type Tail struct {
 	Filename string
 
 	// File-specfic
-	SeekOffset int64 // Seek to this location before tailing
-	SeekWhence int   // Seek from whence. See https://golang.org/pkg/os/#File.Seek
 	ReOpen    bool // Reopen recreated files (tail -F)
 	MustExist bool // Fail early if the file does not exist
 	Poll      bool // Poll for file changes instead of using inotify
 	Pipe      bool // Is a named pipe (mkfifo)
-	// TODO: Add configs for RateLimiter
 
 	// Generic IO
-	Follow      bool // Continue looking for new lines (tail -f)
 	MaxLineSize int // If non-zero, split longer lines into multiple lines
 
 	DisableLogging bool // If false, logs are printed to stderr
@@ -177,15 +164,11 @@ func (t *Tail) Start(acc telegraf.Accumulator) error {
 	t.done = make(chan struct{})
 
 	config := tailfile.Config{
-		Location: &tailfile.SeekInfo{
-			Offset: t.SeekOffset,
-			Whence: t.SeekWhence,
-		},
 		ReOpen:      t.ReOpen,
 		MustExist:   t.MustExist,
 		Poll:        t.Poll,
 		Pipe:        t.Pipe,
-		Follow:      t.Follow,
+		Follow:      true,
 		MaxLineSize: t.MaxLineSize,
 	}
 	if t.DisableLogging {