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tail(1)                          User Commands                         tail(1)



NAME
       tail - deliver the last part of a file

SYNOPSIS
       /usr/bin/tail [ +- number [lbcr]] [file]

       /usr/bin/tail [-lbcr] [file]

       /usr/bin/tail [ +- number [lbcf]] [file]

       /usr/bin/tail [-lbcf] [file]

       /usr/xpg4/bin/tail [-f | -r]  [-c number | -n number]  [file]

       /usr/xpg4/bin/tail [ +- number

        [l | b | c]  [f]] [file]

       /usr/xpg4/bin/tail [ +- number [l]

        [f | r] ] [file]

DESCRIPTION
       The tail utility copies the named file to the standard output beginning
       at a designated place. If no file is named, the standard input is used.

       Copying begins at a point in the file indicated by the -cnumber, -nnum-
       ber,  or  +-number options (if +number is specified, begins at distance
       number from the beginning; if -number is specified, from the end of the
       input;  if  number is NULL, the value 10 is assumed). number is counted
       in units of lines or byte according to  the  -c   or   -n  options,  or
       lines,  blocks,  or bytes, according to the appended option l, b, or c.
       When no units are specified, counting is by lines.

OPTIONS
       The  following  options  are  supported  for  both  /usr/bin/tail   and
       /usr/xpg4/bin/tail.  The  -r  and -f options are mutually exclusive. If
       both are specified on the command line, the -f option will be ignored.

       -b       Units of blocks.



       -c       Units of bytes.



       -f       Follow. If the input-file is not a pipe, the program will  not
                terminate  after  the  line of the input-file has been copied,
                but will enter an endless loop, wherein it sleeps for a second
                and  then  attempts  to read and copy further records from the
                input-file. Thus it may be used to monitor  the  growth  of  a
                file that is being written by some other process.



       -l       Units of lines.



       -r       Reverse. Copies lines from the specified starting point in the
                file in reverse order. The default  for  r  is  to  print  the
                entire file in reverse order.



   /usr/xpg4/bin/tail
       The following options are supported for /usr/xpg4/bin/tail only:

       -c number       The  number  option-argument  must be a decimal integer
                       whose sign affects the location in the  file,  measured
                       in bytes, to begin the copying:


                       +        Copying  starts  relative  to the beginning of
                                the file.




                       -        Copying starts relative  to  the  end  of  the
                                file.



                       none     Copying  starts  relative  to  the  end of the
                                file.


                       The origin for counting is 1; that is, -c+1  represents
                       the first byte of the file, -c-1 the last.


       -n number       Equivalent to -cnumber, except the starting location in
                       the file is measured in lines  instead  of  bytes.  The
                       origin  for counting is 1. That is, -n+1 represents the
                       first line of the file, -n-1 the last.



OPERANDS
       The following operand is supported:

       file     A path name of an input file. If no file operands  are  speci-
                fied, the standard input will be used.



USAGE
       See  largefile(5)  for  the  description  of  the behavior of tail when
       encountering files greater than or equal to 2 Gbyte ( 2**31 bytes).

EXAMPLES
       Example 1: Using the tail Command

       The following command will print the last ten lines of the  file  fred,
       followed  by  any lines that are appended to fred between the time tail
       is initiated and killed.

       example% tail -f fred

       The next command will print the last 15 bytes of the  file  fred,  fol-
       lowed  by  any lines that are appended to fred between the time tail is
       initiated and killed:

       example% tail -15cf fred

ENVIRONMENT VARIABLES
       See environ(5) for descriptions of the following environment  variables
       that affect the execution of tail: LANG, LC_ALL, LC_CTYPE, LC_MESSAGES,
       and NLSPATH.

EXIT STATUS
       The following exit values are returned:

       0        Successful completion.



       >>0       An error occurred.



ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:

   /usr/bin/tail
       tab()    allbox;    cw(2.750000i)|     cw(2.750000i)     lw(2.750000i)|
       lw(2.750000i).    ATTRIBUTE   TYPEATTRIBUTE  VALUE  AvailabilitySUNWcsu
       CSIEnabled


   /usr/xpg4/bin/tail
       tab()    allbox;    cw(2.750000i)|     cw(2.750000i)     lw(2.750000i)|
       lw(2.750000i).    ATTRIBUTE  TYPEATTRIBUTE  VALUE  AvailabilitySUNWxcu4
       CSIEnabled Interface StabilityStandard


SEE ALSO
       cat(1), head(1), more(1),  pg(1),  dd(1M),  attributes(5),  environ(5),
       largefile(5), standards(5)

NOTES
       Piped tails relative to the end of the file are stored in a buffer, and
       thus are limited in length. Various kinds  of  anomalous  behavior  may
       happen with character special files.



SunOS 5.10                        18 Mar 1997                          tail(1)