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.