join — join lines of two files on a common field
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.
also print unpairable lines from file FILENUM, where FILENUM is 1 or 2, corresponding to FILE1 or FILE2
replace missing input fields with EMPTY
ignore differences in case when comparing fields
equivalent to '−1 FIELD −2 FIELD'
obey FORMAT while constructing output line
use CHAR as input and output field separator
but suppress joined output lines
join on this FIELD of file 1
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
line delimiter is NUL, not newline
display this help and exit
output version information and exit
−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
Important: FILE1 and FILE2 must be sorted on the join
fields. E.g., use "sort
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.
GNU coreutils online help: <http://www.gnu.org/software/coreutils/>
Report join translation bugs to <http://translationproject.org/team/>
Full documentation at: <http://www.gnu.org/software/coreutils/join>
or available locally via: info '(coreutils) join invocation'
Copyright © 2015 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.