tail — output the last part of files
tail
[OPTION
...] [FILE
...]
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; or use −c
+K to output bytes starting
with the Kth of each file
−f
, −−follow[=
{name|descriptor}]output appended data as the file grows;
an absent option argument means 'descriptor'
−F
same as −−follow
=name
−−retry
−n
, −−lines
=K
output the last K lines, instead of the last 10; or
use −n
+K to output
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); with inotify, this option is rarely useful
−−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 if it is inaccessible
−s
, −−sleep−interval
=N
with −f
, sleep for
approximately N seconds (default 1.0) between
iterations; with inotify and −−pid
=P
, check process P at least once
every N seconds
−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 in a way that accommodates
renaming, removal and creation.
GNU coreutils online help: <http://www.gnu.org/software/coreutils/>
Report tail translation bugs to <http://translationproject.org/team/>
Full documentation at: <http://www.gnu.org/software/coreutils/tail>
or available locally via: info '(coreutils) tail invocation'
COPYRIGHT |
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Copyright © 2015 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. |