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 tail(1)							     tail(1)




 NAME
      tail - deliver the last part of a file

 SYNOPSIS
      tail [-f] [-b number] [file]

      tail [-f] [-c number] [file]

      tail [-f] [-n number] [file]

    Obsolescent:
      tail [+-[number][l|b|c] [-f] [file]

 DESCRIPTION
      tail copies the named file to the standard output beginning at a
      designated place.	 If no file is named, standard input is used.

    Command Forms
      tail can be used in three forms as indicated above:

	   tail -b number...	 Copy file starting at number blocks from
				 end or beginning of file.

	   tail -c number...	 Copy file starting at number bytes from end
				 or beginning of file.

	   tail -n number...
	   tail number...	 Copy file starting at number lines from end
				 or beginning of file.

      tail with no options specified is equivalent to tail -n 10....

    Options and Command-Line Arguments
      tail recognizes the following options and command-line arguments:

	   -f		  Follow option.  If the input file is a regular
			  file or if file specifies a FIFO, do not terminate
			  after the last line of the input file has been
			  copied, but read and copy further bytes from the
			  input file when they become available (tail enters
			  an endless loop wherein it sleeps for one second
			  then attempts to read and copy further records
			  from the input file).	 This is useful when
			  monitoring text being written to a file by another
			  process.  If no file argument is specified and the
			  input is a pipe (FIFO), the -f option is ignored.

	   number	  Decimal integer indicating quantity of output to
			  be copied, measured in units specified by
			  accompanying option.	If number is preceded by a +
			  character, copy operation starts number units from



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 tail(1)							     tail(1)




			  beginning of file.  If number is preceded by a -
			  character or the option name, copy operation
			  starts number units from end of file.	 If number
			  is not preceded by a b, c, or n option, -n is
			  assumed.  If both the option and number are not
			  specified, -n 10 is assumed.

	   -b number	  Copy file beginning number 512-byte blocks from
			  end or beginning of file.  If number is not
			  specified, -b 10 is assumed.	See number
			  description above.

	   -c number	  Copy file beginning number bytes from end or
			  beginning of file.  If number is not specified, -c
			  10 is assumed.  See number description above.

	   -n number	  Copy file beginning number lines from end or
			  beginning of file.  If number is not specified, -n
			  10 is assumed.  See number description above.

	   file		  Name of file to be copied.  If not specified, the
			  standard input is used.

      If the -c option is specified, the input file can contain arbitrary
      data.  Otherwise, the input file should be a text file.

    Obsolescent Form
      In the obsolescent form, option letters can be concatenated after the
      number argument to select blocks, bytes, or lines.  If this syntax is
      used, +-number must be the first argument given.	If number is not
      specified, -10 is assumed.  This version is provided for backward
      compatibility only.  The forms discussed previously are recommended
      for portability.

 EXTERNAL INFLUENCES
    Environment Variables
      LC_CTYPE determines the locale for the interpretation of sequences of
      bytes of text data as characters (e.g., single- versus multibyte
      characters in arguments and input files).

      LC_MESSAGES determines the language in which messages are displayed.

      If LC_CTYPE or LC_MESSAGES is not specified in the environment or is
      set to the empty string, the value of LANG is used as a default for
      each unspecified or empty variable.  If LANG is not specified or is
      set to the empty string, a default of "C" (see lang(5)) is used
      instead of LANG.

      If any internationalization variable contains an invalid setting, tail
      behaves as if all internationalization variables are set to "C".	See
      environ(5).



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 tail(1)							     tail(1)




    International Code Set Support
      Single- and multi-byte character code sets are supported.	 However,
      the b and c options can break multi-byte characters and should be used
      with caution in a multi-byte locale environment.

 EXAMPLES
      Print the last three lines in file file1 to the standard output, and
      leave tail in ``follow'' mode:

	   tail -fn 3 file1
	   tail -3 -f file1

      Print the last 15 bytes of file logfile followed by any lines that are
      appended to logfile after tail is initiated until it is killed:

	   tail -fc15 logfile
	   tail -f -c 15 logfile

      Three ways to print an entire file:

	   tail -b +1 file
	   tail -c +1 file
	   tail -n +1 file

 WARNINGS
      Tails relative to end-of-file are stored in a 20-Kbyte buffer, and
      thus are limited in length.  Therefore, be wary of the results when
      piping output from other commands into tail.

      Various kinds of anomalous behavior may occur with character special
      files.

 SEE ALSO
      dd(1), head(1).

 STANDARDS CONFORMANCE
      tail: SVID2, SVID3, XPG2, XPG3, XPG4, POSIX.2

















 Hewlett-Packard Company	    - 3 -   HP-UX Release 11i: November 2000