tail - Man Page
output the last part of files
Examples (TL;DR)
- Show last 'count' lines in file:
tail --lines count path/to/file
- Print a file from a specific line number:
tail --lines +count path/to/file
- Print a specific count of bytes from the end of a given file:
tail --bytes count path/to/file
- Print the last lines of a given file and keep reading it until
Ctrl + C
:tail --follow path/to/file
- Keep reading file until
Ctrl + C
, even if the file is inaccessible:tail --retry --follow path/to/file
- Show last 'num' lines in 'file' and refresh every 'n' seconds:
tail --lines count --sleep-interval seconds --follow path/to/file
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=[+]NUM
output the last NUM bytes; or use -c +NUM to output starting with byte NUM of each file
- -f, --follow[={name|descriptor}]
output appended data as the file grows;
an absent option argument means 'descriptor'
- -F
- -n, --lines=[+]NUM
output the last NUM lines, instead of the last 10; or use -n +NUM to skip NUM-1 lines at the start
- --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; can be repeated to watch multiple processes
- -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
- -z, --zero-terminated
line delimiter is NUL, not newline
- --help
display this help and exit
- --version
output version information and exit
NUM 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, R, Q. Binary prefixes can be used, too: KiB=K, MiB=M, and so on.
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.
Author
Written by Paul Rubin, David MacKenzie, Ian Lance Taylor, and Jim Meyering.
Reporting Bugs
GNU coreutils online help: <https://www.gnu.org/software/coreutils/>
Report any translation bugs to <https://translationproject.org/team/>
Copyright
Copyright © 2024 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://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
Full documentation <https://www.gnu.org/software/coreutils/tail>
or available locally via: info '(coreutils) tail invocation'
Referenced By
collectd.conf(5), ctail(1), e2tail(1), fetchlog(1), head(1), ii(1), pmcd(1), pmdalogger(1), pmdasystemd(1), pmdaweblog(1), sdjournal(1), since(1), swatch(1), swatchdog(1), virt-tail(1).