`cdx join [options…] file_1 file_2
| -a | –also=FileNum,FileName | Write non-matching lines from this file to this file. |
| -f | –file=FileName | Write matching lines to this file, default is “-“ for stdout |
| -k | –key Spec | How to compare adjacent lines. Spec is any of the standard Comparisons |
| -o | –output=Spec | Output Columns. See below. |
Output Columns are a comma delimited list of Column Sets.
The first item in the list must be prefixed with a file number, followed by a period, e.g. 1.2 refers to the second column of the first file.
Other items in the list may be prefixed by a file number. If not, the previously specified column number is assumed, e.g. 2.1-3,~2,1.3,1.1 indicates
columns 1 and 3 from the second file, followed by columns 3 and 1 from the first file. -o 1.1,2.2 is the same as -o 1.1 -o 2.2.