ARR(1)                      General Commands Manual                     ARR(1)

NAME
     arr – (re)arrange and select fields on each line

SYNOPSIS
     arr [-0] [-P | -p padding] expr [files ...]

DESCRIPTION
     arr unifies and extends the features of cut(1), paste(1), and provides an
     alternative to dicer(5).

     arr will read one line (or zero separated string, when -0 is used) from
     each file passed on the command line, and then print the result of
     expanding expr.

     By default, reading continues until all files are exhausted.  Ended files
     continue generating empty strings, or padding when -p is used.  When -P
     is used, reading stops as soon as one file is exhausted.

FORMATTING EXPRESSIONS
     expr is read as a string containing escape sequences ‘%{...}’ which are
     parsed according to the following EBNF:

           <expr>   ::= <fields> (("|" <char> | "*") <fields>)* ("&" <char>)?
           <fields> ::= "~"? <field> ("," <field>)*
           <field>  ::= "-"? ""+ | ("-"? ""+)? ":" ("-"? ""+)?

     Fields are specified by their position, negative numbers count from the
     end.  Field ranges are written like n:m where n and m are optional and
     default to 1 and -1 respectively.  If n is bigger than m, fields are
     expanded in reverse order.

     Field ranges are combined using , and an initial ~ negates the whole set
     of field selections.

     Selected fields are joined with the last separator, and then split on c
     when |c is used.  Alternatively, * splits byte-wise.  A final &c joins
     the selected fields using c again.

     The first set of fields corresponds to the lines read from each file.

EXIT STATUS
     The arr utility exits 0 on success, and >0 if an error occurs.

EXAMPLES
     Print all users from /etc/passwd (read: ‘take line from file 1, split on
     :, print field 1.’):

           arr '%{1|:1}' /etc/passwd

     List all basenames of shells used (read ‘take line from file 1, split on
     :, take last field, split on /, take last field.’):

           arr '%{1|:-1|/-1}' /etc/passwd | sort -u

     Remove the TLD from a list of domains:

           arr '%{1|.~-1}'

     Generate PTR addresses for a list of IPv4s:

           arr '%{1|.-1:1}.in-addr.arpa'

     Only print the first 80 chars of each line:

           arr '%{1*:80}'

     Double space text:

           arr '%{1*:& }'

     Format a phone number:

           echo 8005551212 | arr '(%{1*1:3})%{1*4:6}-%{1*7:}'

SEE ALSO
     cut(1), paste(1), dicer(5)

AUTHORS
     Christian Neukirchen <chneukirchen@gmail.com>

LICENSE
     arr is in the public domain.

     To the extent possible under law, the creator of this work has waived all
     copyright and related or neighboring rights to this work.

     http://creativecommons.org/publicdomain/zero/1.0/

Linux 4.3.4_1                  February 14, 2016                 Linux 4.3.4_1