join -- Join two data bases

join [-a [n] ] [-e string ] [-j[n] keyf] [-o n.m ...] [-tc] file1 file2

Options:
     -a[n]     Print unpaired records from file n
     -e s      Replace empty fields on output with string s
     -j[n] key Use key of file n for comparison
     -o [n.]m ..
               Subsequent arguments list fields to output; each has file n and
               field number m
     -tc       Field separator is character c

If either file1 or file2 is `-', stdin is used.  The optional file n may be
either 1 or 2; if omitted, both 1 and 2 are assumed.
					

© 2012 by Stephen A. Ness