Интерактивная система просмотра системных руководств (man-ов)
tail (1)
tail (1) ( Solaris man: Команды и прикладные программы пользовательского уровня )
>> tail (1) ( FreeBSD man: Команды и прикладные программы пользовательского уровня )
tail (1) ( Русские man: Команды и прикладные программы пользовательского уровня )
tail (1) ( Linux man: Команды и прикладные программы пользовательского уровня )
tail (1) ( POSIX man: Команды и прикладные программы пользовательского уровня )
BSD mandoc
NAME
tail
- display the last part of a file
SYNOPSIS
[-F | f | r
]
[-q
]
[-b number | -c number | -n number
]
[file ...
]
DESCRIPTION
The
utility displays the contents of
file
or, by default, its standard input, to the standard output.
The display begins at a byte, line or 512-byte block location in the
input.
Numbers having a leading plus
(`+'
)
sign are relative to the beginning
of the input, for example,
``-c +2
''
starts the display at the second
byte of the input.
Numbers having a leading minus
(`-'
)
sign or no explicit sign are
relative to the end of the input, for example,
``-n 2
''
displays the last two lines of the input.
The default starting location is
``-n 10
''
or the last 10 lines of the input.
The options are as follows:
-b number
The location is
number
512-byte blocks.
-c number
The location is
number
bytes.
-f
The
-f
option causes
to not stop when end of file is reached, but rather to wait for additional
data to be appended to the input.
The
-f
option is ignored if the standard input is a pipe, but not if it is a FIFO.
-F
The
-F
option implies the
-f
option, but
will also check to see if the file being followed has been renamed or rotated.
The file is closed and reopened when
detects that the filename being read from has a new inode number.
The
-F
option is ignored if reading from standard input rather than a file.
-n number
The location is
number
lines.
-q
Suppresses printing of headers when multiple files are being examined.
-r
The
-r
option causes the input to be displayed in reverse order, by line.
Additionally, this option changes the meaning of the
-b , c
and
-n
options.
When the
-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
-r
option is to display all of the input.
If more than a single file is specified, each file is preceded by a
header consisting of the string
``==> XXX <==
''
where
XXX
is the name of the file unless
-q
flag is specified.
The
utility is expected to be a superset of the
St -p1003.2-92
specification.
In particular, the
-F
-b
and
-r
options are extensions to that standard.
The historic command line syntax of
is supported by this implementation.
The only difference between this implementation and historic versions
of
,
once the command line syntax translation has been done, is that the
-b
-c
and
-n
options modify the
-r
option, i.e.,
``-r -c 4
''
displays the last 4 characters of the last line
of the input, while the historic tail (using the historic syntax
``-4cr
''
would ignore the
-c
option and display the last 4 lines of the input.
