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(textutils.info)uniq invocation

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`uniq': Uniquify files
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   `uniq' writes the unique lines in the given `input', or standard
input if nothing is given or for an INPUT name of `-'.  Synopsis:

     uniq [OPTION]... [INPUT [OUTPUT]]

   By default, `uniq' prints the unique lines in a sorted file, i.e.,
discards all but one of identical successive lines.  Optionally, it can
instead show only lines that appear exactly once, or lines that appear
more than once.

   The input must be sorted.  If your input is not sorted, perhaps you
want to use `sort -u'.

   If no OUTPUT file is specified, `uniq' writes to standard output.

   Fields are sequences of non-space non-tab characters that are
separated from each other by at least one spaces or tabs, unless a
separator is given.

   The program accepts the following options.  Also see Note: Common
options.

`-N'
`-f N'
`--skip-fields=N'
     Skip N fields on each line before checking for uniqueness.

`+N'
`-s N'
`--skip-chars=N'
     Skip N characters before checking for uniqueness.  If you use both
     the field and character skipping options, fields are skipped over
     first.

`-c'
`--count'
     Print the number of times each line occurred along with the line.

`-i'
`--ignore-case'
     Ignore differences in case when comparing lines.

`-d'
`--repeated'
     Print only duplicate lines.

`-D'
`--all-repeated'
     Print all duplicate lines and only duplicate lines.  This option
     is useful mainly in conjunction with other options e.g., to ignore
     case or to compare only selected fields.  This is a GNU extension.

`-u'
`--unique'
     Print only unique lines.

`-t SEP'
`--separator=SEP'
     Use SEP to delimit fields.

`-w N'
`--check-chars=N'
     Compare no more than N characters on each line (after skipping any
     specified fields and characters).  By default the entire rest of
     the lines are compared.

`-W N'
`--check-fields=N'
     Compare no more than N fields on each line (after skipping any
     specified fields and characters).  By default the entire rest of
     the lines are compared.