HP-UX Reference (11i v2 07/12) - 1 User Commands N-Z (vol 2)
t
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]][
lbc][-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 ter-
minate 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 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.
326 Hewlett-Packard Company − 1 − HP-UX 11i Version 2: December 2007 Update