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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. |
−−retry |
keep trying to open a file even if it is inaccessible when tail starts or if it becomes inaccessible later −− useful only with −f |
−c, −−bytes=N |
output the last N bytes |
−f, −−follow[={name|descriptor}] output appended data as the file grows; |
−f, −−follow, and −−follow=descriptor are equivalent |
−n, −−lines=N |
output the last N lines, instead of the last 10 |
−−max−unchanged−stats=N see the texinfo documentation |
(the default is 5) |
−−max−consecutive−size−changes=N see the texinfo documentation |
(the default is 200) |
−−pid=PID |
with −f, terminate after process ID, PID dies |
−q, −−quiet, −−silent |
never output headers giving file names |
−s, −−sleep−interval=S |
with −f, sleep S seconds 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 N (the number of bytes or lines) is a ‘+’, print beginning with the Nth item from the start of each file, otherwise, print the last N items in the file. N may have a multiplier suffix: b for 512, k for 1024, m for 1048576 (1 Meg). A first OPTION of −VALUE or +VALUE is treated like −n VALUE or −n +VALUE unless VALUE has one of the [bkm] suffix multipliers, in which case it is treated like −c VALUE or −c +VALUE. 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. |
Written by Paul Rubin, David MacKenzie, Ian Lance Taylor, and Jim Meyering. |
Report bugs to <bug-textutils@gnu.org>. |
Copyright © 1999 Free Software Foundation, Inc. |
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 tail |
should give you access to the complete manual. |