TAIL

Section: User Commands (1)
Updated: December 2009
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NAME

tail - output the last part of files  

SYNOPSIS

tail [OPTION]... [FILE]...  

DESCRIPTION

Print the last 10 lines of each FILE to standard output. With more than one FILE, precede each with a header giving the file name. With no FILE, or when FILE is -, read standard input.

Mandatory arguments to long options are mandatory for short options too.

-c, --bytes=K
output the last K bytes; alternatively, use +K to output bytes starting with the Kth of each file
-f, --follow[={name|descriptor}]
output appended data as the file grows; -f, --follow, and --follow=descriptor are equivalent
-F
same as --follow=name --retry
-n, --lines=K
output the last K lines, instead of the last 10; or use +K to output lines starting with the Kth
--max-unchanged-stats=N
with --follow=name, reopen a FILE which has not changed size after N (default 5) iterations to see if it has been unlinked or renamed (this is the usual case of rotated log files)
--pid=PID
with -f, terminate after process ID, PID dies
-q, --quiet, --silent
never output headers giving file names
--retry
keep trying to open a file even when it is or becomes inaccessible; useful when following by name, i.e., with --follow=name
-s, --sleep-interval=N
with -f, sleep for approximately N seconds (default 1.0) between iterations
-v, --verbose
always output headers giving file names
--help
display this help and exit
--version
output version information and exit

If the first character of K (the number of bytes or lines) is a `+', print beginning with the Kth item from the start of each file, otherwise, print the last K items in the file. K may have a multiplier suffix: b 512, kB 1000, K 1024, MB 1000*1000, M 1024*1024, GB 1000*1000*1000, G 1024*1024*1024, and so on for T, P, E, Z, Y.

With --follow (-f), tail defaults to following the file descriptor, which means that even if a tail'ed file is renamed, tail will continue to track its end. This default behavior is not desirable when you really want to track the actual name of the file, not the file descriptor (e.g., log rotation). Use --follow=name in that case. That causes tail to track the named file by reopening it periodically to see if it has been removed and recreated by some other program.  

AUTHOR

Written by Paul Rubin, David MacKenzie, Ian Lance Taylor, and Jim Meyering.  

REPORTING BUGS

Report tail bugs to bug-coreutils@gnu.org
GNU coreutils home page: <http://www.gnu.org/software/coreutils/>
General help using GNU software: <http://www.gnu.org/gethelp/>  

COPYRIGHT

Copyright © 2009 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.  

SEE ALSO

The full documentation for tail is maintained as a Texinfo manual. If the info and tail programs are properly installed at your site, the command
info coreutils aqtail invocationaq

should give you access to the complete manual.