TAIL

NAME
SYNOPSIS
DESCRIPTION

NAME

tail - output the last part of files

SYNOPSIS

tail [-c [+]N[bkm]] [-n [+]N] [-fqv] [--bytes=[+]N[bkm]] [--lines=[+]N] [--follow] [--quiet] [--silent] [--verbose] [--help] [--version] [file...]

tail [{-,+}Nbcfklmqv] [file...]

DESCRIPTION

This documentation is no longer being maintained and may be inaccurate or incomplete. The Texinfo documentation is now the authoritative source.

This manual page documents the GNU version of tail. tail prints the last part (10 lines by default) of each given file; it reads from standard input if no files are given or when a filename of ’-’ is encountered. If more than one file is given, it prints a header consisting of the file’s name enclosed in ’==>’ and ’<==’ before the output for each file.

The GNU tail can output any amount of data, unlike the Unix version, which uses a fixed size buffer. It has no -r option (print in reverse). Reversing a file is really a different job from printing the end of a file; the BSD tail can only reverse files that are at most as large as its buffer, which is typically 32k. A reliable and more versatile way to reverse files is the GNU tac command.

OPTIONS
tail
accepts two option formats: the new one, in which numbers are arguments to the option letters, and the old one, in which a ’+’ or ’-’ and optional number precede any option letters.

If a number (’N’) starts with a ’+’, tail begins printing with the Nth item from the start of each file, instead of from the end.
-c N, --bytes N

Tail by N bytes. N is a nonzero integer, optionally followed by one of the following characters to specify a different unit.

b

512-byte blocks.

k

1-kilobyte blocks.

m

1-megabyte blocks.

-f, --follow

Loop forever trying to read more characters at the end of the file, on the assumption that the file is growing. Ignored if reading from a pipe. If more than one file is given, tail prints a header whenever it gets output from a different file, to indicate which file that output is from.

-l, -n N, --lines N

Tail by N lines. -l is only recognized using the old option format.

-q, --quiet, --silent

Never print filename headers.

-v, --verbose

Always print filename headers.

--help

Print a usage message and exit with a status code indicating success.

--version

Print version information on standard output then exit.