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+.\" Copyright (c) 1980, 1990, 1991, 1993
+.\"	The Regents of the University of California.  All rights reserved.
+.\"
+.\" This code is derived from software contributed to Berkeley by
+.\" the Institute of Electrical and Electronics Engineers, Inc.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.Dd November 28, 2023
+.Dt TAIL 1
+.Os
+.Sh NAME
+.Nm tail
+.Nd display the last part of a file
+.Sh SYNOPSIS
+.Nm
+.Op Fl F | f | r
+.Op Fl qv
+.Oo
+.Fl b Ar number | Fl c Ar number | Fl n Ar number
+.Oc
+.Op Ar
+.Sh DESCRIPTION
+The
+.Nm
+utility displays the contents of
+.Ar file
+or, by default, its standard input, to the standard output.
+.Pp
+The display begins at a byte, line or 512-byte block location in the
+input.
+Numbers having a leading plus
+.Pq Ql +
+sign are relative to the beginning
+of the input, for example,
+.Dq Li "-c +2"
+starts the display at the second
+byte of the input.
+Numbers having a leading minus
+.Pq Ql -
+sign or no explicit sign are
+relative to the end of the input, for example,
+.Dq Li "-n 2"
+displays the last two lines of the input.
+The default starting location is
+.Dq Li "-n 10" ,
+or the last 10 lines of the input.
+.Pp
+The options are as follows:
+.Bl -tag -width indent
+.It Fl b Ar number , Fl -blocks Ns = Ns Ar number
+The location is
+.Ar number
+512-byte blocks.
+.It Fl c Ar number , Fl -bytes Ns = Ns Ar number
+The location is
+.Ar number
+bytes.
+.It Fl f
+The
+.Fl f
+option causes
+.Nm
+to not stop when end of file is reached, but rather to wait for additional
+data to be appended to the input.
+The
+.Fl f
+option is ignored if the standard input is a pipe, but not if it is a FIFO.
+.It Fl F
+The
+.Fl F
+option implies the
+.Fl f
+option, but
+.Nm
+will also check to see if the file being followed has been renamed or rotated.
+The file is closed and reopened when
+.Nm
+detects that the filename being read from has a new inode number.
+.Pp
+If the file being followed does not (yet) exist or if it is removed, tail
+will keep looking and will display the file from the beginning if and when
+it is created.
+.Pp
+The
+.Fl F
+option is the same as the
+.Fl f
+option if reading from standard input rather than a file.
+.It Fl n Ar number , Fl -lines Ns = Ns Ar number
+The location is
+.Ar number
+lines.
+.It Fl q , Fl -quiet , Fl -silent
+Suppresses printing of headers when multiple files are being examined.
+.It Fl r
+The
+.Fl r
+option causes the input to be displayed in reverse order, by line.
+Additionally, this option changes the meaning of the
+.Fl b , c
+and
+.Fl n
+options.
+When the
+.Fl r
+option is specified, these options specify the number of bytes, lines
+or 512-byte blocks to display, instead of the bytes, lines or blocks
+from the beginning or end of the input from which to begin the display.
+The default for the
+.Fl r
+option is to display all of the input.
+.It Fl v , Fl -verbose
+Prepend each file with a header.
+.El
+.Pp
+If more than a single file is specified, or if the
+.Fl v
+option is used, each file is preceded by a
+header consisting of the string
+.Dq Li "==> " Ns Ar XXX Ns Li " <=="
+where
+.Ar XXX
+is the name of the file.
+The
+.Fl q
+flag disables the printing of the header in all cases.
+.Pp
+All
+.Ar number
+arguments may also be specified with size suffixes supported by
+.Xr expand_number 3 .
+.Sh EXIT STATUS
+.Ex -std
+.Sh EXAMPLES
+Display the last 500 lines of the file
+.Ar foo :
+.Pp
+.Dl $ tail -n 500 foo
+.Pp
+Keep
+.Pa /var/log/messages
+open, displaying to the standard output anything appended to the file:
+.Pp
+.Dl $ tail -F /var/log/messages
+.Pp
+Read
+.Pa /var/log/messages
+from the beginning and then follow the file as usual:
+.Pp
+.Dl $ tail -F -n +1 /var/log/messages
+.Sh SEE ALSO
+.Xr cat 1 ,
+.Xr head 1 ,
+.Xr sed 1 ,
+.Xr expand_number 3
+.Sh STANDARDS
+The
+.Nm
+utility is expected to be a superset of the
+.St -p1003.2-92
+specification.
+In particular, the
+.Fl F ,
+.Fl b
+and
+.Fl r
+options are extensions to that standard.
+.Pp
+The historic command line syntax of
+.Nm
+is supported by this implementation.
+The only difference between this implementation and historic versions
+of
+.Nm ,
+once the command line syntax translation has been done, is that the
+.Fl b ,
+.Fl c
+and
+.Fl n
+options modify the
+.Fl r
+option, i.e.,
+.Dq Li "-r -c 4"
+displays the last 4 characters of the last line
+of the input, while the historic tail (using the historic syntax
+.Dq Li -4cr )
+would ignore the
+.Fl c
+option and display the last 4 lines of the input.
+.Sh HISTORY
+A
+.Nm
+command appeared in PWB UNIX.