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tail(1)								      tail(1)



NAME

  tail - Writes	a file to standard output, beginning at	a specified point

SYNOPSIS

  tail [-f  | -r] [-c number | -n number] [file]

  tail [+number	| -number] [unit] [-f  | -r] [file]

  The tail command writes the named file (standard input by default) to	stan-
  dard output, beginning at a point you	specify.

  The second synopsis form of this command is obsolete,	and support may	be
  withdrawn at any time.

STANDARDS

  Interfaces documented	on this	reference page conform to industry standards
  as follows:

  tail:	 XCU5.0

  Refer	to the standards(5) reference page for more information	about indus-
  try standards	and associated tags.

OPTIONS

  -c number
      Displays the remainder of	the file from the starting point number	where
      number is	measured in bytes. The sign of number affects the location in
      the file at which	to begin the copying:

      +	(plus sign)
	  Copying begins relative to the beginning of the file.

      -	(minus sign)
	  Copying begins relative to the end of	the file.

      no sign
	  Copying begins relative to the end of	the file.

      The origin for counting is 1, that is, -c	+1 represents the first	byte
      of the file, -c -1 the last.

  -f  Does not end after it copies the last line of the	input file if the
      input file is not	read from a pipe, but enters an	endless	loop in	which
      it sleeps	for a second and then attempts to read and copy	further
      records from the input file.  Thus, it can be used to monitor the
      growth of	a file being written by	another	process.  Has no effect	if
      specified	with -r.

  -n number
      Displays remainder of file from the starting point number	where number
      is measured in lines.  The sign of number	affects	the location in	the
      file, measured in	lines, to begin	the copying:

      +	(plus) sign
	  Copying begins relative to the beginning of the file.

      -	(minus)	sign
	  Copying begins relative to the end of	the file.

      no sign
	  Copying begins relative to the end of	the file.

      The origin for counting is 1, that is, -n	+1 represents the first	line
      of the file, -n -1 the last.

  -r  [Tru64 UNIX]  Causes tail	to print lines from the	end of the file	in
      reverse order.  The default for -r is to print the entire	file this
      way.  Overrides -f.

  -[number]l

  -[number]b

  -[number]k

  -[number]c

  -[number]m
      Begins reading number lines (l), 512-byte	blocks (b), kilobyte blocks
      (k), characters (c and m)	from the end of	the input.  The	m argument
      counts mulktibyte	characters as single-byte characters, while c counts
      characters byte-by-byte but does not break mulktibyte characters.

      The default unit is l for	lines. The default number is 10	for all
      units.

  +[number]l

  +[number]b

  +[number]k

  +[number]c

  +[number]m
      Begins reading number lines (l), 512-byte	blocks (b), 1-kilobyte blocks
      (k), or characters (c and	m) from	the beginning of the input.  The m
      argument counts mulktibyte characters as single-byte characters, while
      c	counts characters byte-by-byte but does	not break mulktibyte charac-
      ters.

      The default unit is l for	lines. The default number is 10	for all
      units.

  In the non-obsolescent form, if you do not specify either -c or n, -n	10 is
  the default.

DESCRIPTION

  If you do not	specify	-f, -r,	-number, or +number, tail begins reading 10
  lines	before the end of the file. The	default	starting point is - (end of
  input), l (lines) is the default unit, and 10	is the default number.

  By specifying	+, you can direct tail to read from the	beginning of the
  file.	 By specifying a number	or a unit, or both, you	can change the point
  at which tail	begins reading.

  [Tru64 UNIX]	The unit argument can specify lines, blocks, or	characters.
  The tail command can begin reading number (10	by default) units from either
  the end or the beginning of the file.

  [Tru64 UNIX]	The block size is either 512 bytes or 1	kilobyte.

NOTES

  When the input is a text file	containing mulktibyte characters, use the -c
  option cautiously since the output produced may not start on a character
  boundary.

EXIT STATUS

  The following	exit values are	returned:

  0   Successful completion.

  >>0  An error occurred.

EXAMPLES

   1.  To display the last 10 lines of a file named notes, enter:
	    tail notes

   2.  To specify how far from the end to start, enter:
	    tail -20 notes

       This displays the last 20 lines of notes.

   3.  To specify how far from the beginning to	start, enter:
	    tail +200c notes | more

       This displays notes a page at a time, starting with the 200th charac-
       ter from	the beginning.

   4.  To follow the growth of a file named accounts, enter:
	    tail -1 -f accounts

       This displays the last line of accounts.	 Once every second, tail
       displays	any lines that have been added to the file. This continues
       until stopped by	pressing the Interrupt key sequence.

ENVIRONMENT VARIABLES

  The following	environment variables affect the execution of tail:

  LANG
      Provides a default value for the internationalization variables that
      are unset	or null. If LANG is unset or null, the corresponding value
      from the default locale is used.	If any of the internationalization
      variables	contain	an invalid setting, the	utility	behaves	as if none of
      the variables had	been defined.

  LC_ALL
      If set to	a non-empty string value, overrides the	values of all the
      other internationalization variables.

  LC_CTYPE
      Determines the locale for	the interpretation of sequences	of bytes of
      text data	as characters (for example, single-byte	as opposed to mulkti-
      byte characters in arguments and input files).

  LC_MESSAGES
      Determines the locale for	the format and contents	of diagnostic mes-
      sages written to standard	error.

  NLSPATH
      Determines the location of message catalogues for	the processing of
      LC_MESSAGES.

SEE ALSO

  Commands:  cat(1), head(1), more(1), page(1),	pg(1)

  Standards:  standards(5)