| -c |
prefix lines by the number of occurrences
|
| -d |
only print duplicate lines, one for each group
|
| -D |
print all duplicate lines
|
| -f N |
avoid comparing the first N fields
|
| -i |
ignore differences in case when comparing
|
| -s N |
avoid comparing the first N characters
|
| -u |
only print unique lines
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| -z |
line delimiter is NUL, not newline
|