GREP(1)             RISC/os Reference Manual              GREP(1)



NAME
     grep - search a file for a pattern

SYNOPSIS
     grep [options] limited regular expression [file ...]

DESCRIPTION
     grep searches files for a pattern and prints all lines that
     contain that pattern.  grep uses limited regular expressions
     (expressions that have string values that use a subset of
     the possible alphanumeric and special characters) like those
     used with ed(1) to match the patterns.  It uses a compact
     non-deterministic algorithm.

     Be careful using the characters $, *, [, ^, |, (, ), and \
     in the limited regular expression because they are also
     meaningful to the shell.  It is safest to enclose the entire
     limited regular expression in single quotes '...'.

     If no files are specified, grep assumes standard input.
     Normally, each line found is copied to standard output.  The
     file name is printed before each line found if there is more
     than one input file.

     Command line options are:

     -b    Precede each line by the block number (512-byte block)
           on which it was found.  This can be useful in locating
           block numbers by context (first block is 0).
     -c    Print only a count of the lines that contain the pat-
           tern.
     -i    Ignore upper/lower case distinction during comparis-
           ons.
     -h    Prevents the name of the file containing the matching
           line from being appended to that line.  Used when
           searching multiple files.
     -l    Print the names of files with matching lines once,
           separated by new-lines.  Does not repeat the names of
           files when the pattern is found more than once.
     -n    Precede each line by its line number in the file
           (first line is 1).
     -s    Suppress error messages about nonexistent or unread-
           able files
     -v    Print all lines except those that contain the pattern.

INTERNATIONAL FUNCTIONALITY
     grep can process characters from supplementary code sets, as
     well as ASCII characters.  Searches are performed on charac-
     ters, not individual bytes.

     The -i option, ignore upper/lower case distinction during
     comparisons, is valid for single byte characters only.



                        Printed 11/19/92                   Page 1

GREP(1)             RISC/os Reference Manual              GREP(1)



SEE ALSO
     ed(1), egrep(1), fgrep(1), sed(1), sh(1).

DIAGNOSTICS
     Exit status is 0 if any matches are found, 1 if none, 2 for
     syntax errors or inaccessible files (even if matches were
     found).

NOTES
     Lines are limited to BUFSIZ characters; longer lines are
     truncated.  BUFSIZ is defined in /usr/include/stdio.h.
     If there is a line with embedded nulls, grep will only match
     up to the first null; if it matches, it will print the
     entire line.









































 Page 2                 Printed 11/19/92