Provided by: coreutils_8.13-3ubuntu3_i386 bug


       join - join lines of two files on a common field


       join [OPTION]... FILE1 FILE2


       For  each  pair of input lines with identical join fields, write a line
       to standard output.  The default join field is the first, delimited  by
       whitespace.  When FILE1 or FILE2 (not both) is -, read standard input.

       -a FILENUM
              print  unpairable  lines coming from file FILENUM, where FILENUM
              is 1 or 2, corresponding to FILE1 or FILE2

       -e EMPTY
              replace missing input fields with EMPTY

       -i, --ignore-case
              ignore differences in case when comparing fields

       -j FIELD
              equivalent to `-1 FIELD -2 FIELD'

       -o FORMAT
              obey FORMAT while constructing output line

       -t CHAR
              use CHAR as input and output field separator

       -v FILENUM
              like -a FILENUM, but suppress joined output lines

       -1 FIELD
              join on this FIELD of file 1

       -2 FIELD
              join on this FIELD of file 2

              check that the input is correctly  sorted,  even  if  all  input
              lines are pairable

              do not check that the input is correctly sorted

              treat  the  first line in each file as field headers, print them
              without trying to pair them

       --help display this help and exit

              output version information and exit

       Unless -t CHAR  is  given,  leading  blanks  separate  fields  and  are
       ignored,  else  fields  are  separated  by  CHAR.  Any FIELD is a field
       number counted from 1.  FORMAT is one or more comma or blank  separated
       specifications,  each  being  `FILENUM.FIELD'  or  `0'.  Default FORMAT
       outputs the join field, the remaining fields from FILE1, the  remaining
       fields  from  FILE2,  all  separated by CHAR.  If FORMAT is the keyword
       'auto', then the first line of  each  file  determines  the  number  of
       fields output for each line.

       Important:  FILE1  and  FILE2 must be sorted on the join fields.  E.g.,
       use ` sort -k 1b,1 ' if `join' has no options, or use ` join -t '' ' if
       `sort'  has no options.  Note, comparisons honor the rules specified by
       `LC_COLLATE'.  If the input is not sorted  and  some  lines  cannot  be
       joined, a warning message will be given.


       Written by Mike Haertel.


       Report join bugs to
       GNU coreutils home page: <>
       General help using GNU software: <>
       Report join translation bugs to <>


       Copyright  ©  2011  Free Software Foundation, Inc.  License GPLv3+: GNU
       GPL version 3 or later <>.
       This is free software: you are free  to  change  and  redistribute  it.
       There is NO WARRANTY, to the extent permitted by law.


       comm(1), uniq(1)

       The  full documentation for join is maintained as a Texinfo manual.  If
       the info and join programs are properly installed  at  your  site,  the

              info coreutils 'join invocation'

       should give you access to the complete manual.