NAME

       tre-agrep - print lines approximately matching a pattern

SYNOPSIS

       tre-agrep [OPTION]...  PATTERN [FILE]...

DESCRIPTION

       Searches  for  approximate  matches  of PATTERN in each FILE or standard input.   Example:
       `tre-agrep -2 optimize foo.txt' outputs all lines in file `foo.txt' that match  "optimize"
       within  two  errors.   E.g.  lines which contain "optimise", "optmise", and "opitmize" all
       match.

OPTIONS

   Regexp selection and interpretation:
       -e PATTERN, --regexp=PATTERN
              Use PATTERN as a regular expression; useful to protect patterns beginning with -.

       -i, --ignore-case
              Ignore case distinctions (as defined by the current locale) in  PATTERN  and  input
              files.

       -k, --literal
              Treat  PATTERN  as  a  literal  string,  that  is,  a  fixed string with no special
              characters.

       -w, --word-regexp
              Force PATTERN to match only whole words.  A  "whole  word"  is  a  substring  which
              either  starts  at  the  beginning  or  the  record  or  is  preceded by a non-word
              constituent character.   Similarly, the substring must either end at the end of the
              record  or  be  followed  by  a  non-word  constituent character.  Word-constituent
              characters are alphanumerics (as defined by the current locale) and the  underscore
              character.   Note that the non-word constituent characters must surround the match;
              they cannot be counted as errors.

   Approximate matching settings:
       -D NUM, --delete-cost=NUM
              Set cost of missing characters to NUM.

       -I NUM, --insert-cost=NUM
              Set cost of extra characters to NUM.

       -S NUM, --substitute-cost=NUM
              Set cost of  incorrect  characters  to  NUM.   Note  that  a  deletion  (a  missing
              character)  and an insertion (an extra character) together constitute a substituted
              character, but the cost will be the that of  a  deletion  and  an  insertion  added
              together.  Thus, if the const of a substitution is set to be larger than the sum of
              the costs of deletion and insertion, direct substitutions will never be done.

       -E NUM, --max-errors=NUM
              Select records that have at most NUM errors.

       -#     Select records that have at most # errors (# is a digit between 0 and 9).

   Miscellaneous:
       -d PATTERN, --delimiter=PATTERN
              Set the record delimiter regular expression  to  PATTERN.   The  text  between  two
              delimiters,  before the first delimiter, and after the last delimiter is considered
              to be a record.  The default record delimiter is the regexp "\n", so by  default  a
              record  is  a  line.  PATTERN can be any regular expression that does not match the
              empty string.  For example, using -d "^From " defines mail messages as records in a
              Mailbox format file.

       -v, --invert-match
              Select non-matching records instead of matching records.

       -V, --version
              Print version information and exit.

       -y, --nothing
              Does  nothing.   This options exists only for compatibility with the non-free agrep
              program.

       --help Display a brief help message and exit.

   Output control:
       -B, --best-match
              Only output the best matching records, that is, the records with the  lowest  cost.
              This  is currently implemented by making two passes over the input files and cannot
              be used when reading from standard input.

       --color, --colour
              Highlight the matching strings in the output with a color marker.  The color string
              is taken from the GREP_COLOR environment variable.  The default color is red.

       -c, --count
              Only  print  a  count  of  matching records per each input file, suppressing normal
              output.

       -h, --no-filename
              Suppress the prefixing filename on output when multiple files are searched.

       -H, --with-filename
              Prefix each output record with the name of the input file where the record was read
              from.

       -l, --files-with-matches
              Only  print  the  name  of  each  input  file  which  contains  at least one match,
              suppressing normal output.  The scanning for each  file  will  stop  on  the  first
              match.

       -n, --record-number
              Prefix  each  output record with its sequence number in the input file.  The number
              of the first record is 1.

       -q, --quiet, --silent
              Do not write anything to standard output.  Exit immediately with zero  exit  status
              if a match is found.

       -s, --show-cost
              Print match cost with output.

       --show-position
              Prefix  each  output record with the start and end offset of the first match within
              the record.  The offset of the first  character  of  the  record  is  0.   The  end
              position is given as the offset of the first character after the match.

       -M, --delimiter-after
              By  default,  the record delimiter is the newline character and is output after the
              matching record.  If -d is used, the record delimiter will  be  output  before  the
              matching  record.  This option causes the delimiter to be output after the matching
              record.

       With no FILE, or when FILE is -, reads standard input.  If less than two FILEs  are  given
       -h is assumed, otherwise -H is the default.

DIAGNOSTICS

       Exit  status  is 0 if a match is found, 1 for no match, and 2 if there were errors.  If -E
       or -# is not specified, only exact matches are selected.

       PATTERN is a POSIX extended regular expression (ERE) with the TRE extensions.

REPORTING BUGS

       Report bugs to the TRE mailing list <tre-general@lists.laurikari.net>.

COPYRIGHT

       Copyright © 2002-2004 Ville Laurikari.
       This is free software, and  comes  with  ABSOLUTELY  NO  WARRANTY.   You  are  welcome  to
       redistribute  this  software under certain conditions; see the source for the full license
       text.