Fsdb::Filter::dbrow

NAME

dbrow - select rows from an Fsdb file based on arbitrary conditions

SYNOPSIS

dbrow [-vw] CONDITION [ CONDITION... ]

DESCRIPTION

Select rows for which all CONDITIONS are true. Conditions are specified as Perl code, in which column names are be embedded, preceded by underscores.

OPTIONS

This module also supports the standard fsdb options:

-w or --warnings

Enable warnings in user supplied code.

-i or --input InputSource

Read from InputSource, typically a file name, or "-" for standard input, or (if in Perl) a IO::Handle, Fsdb::IO or Fsdb::BoundedQueue objects.

-o or --output OutputDestination

Write to OutputDestination, typically a file name, or "-" for standard output, or (if in Perl) a IO::Handle, Fsdb::IO or Fsdb::BoundedQueue objects.

--autorun or --noautorun

By default, programs process automatically, but Fsdb::Filter objects in Perl do not run until you invoke the run() method. The "--(no)autorun" option controls that behavior within Perl.

--header H

Use H as the full Fsdb header, rather than reading a header from then input.

--help

Show help.

--man

Show full manual.

SAMPLE USAGE

Input:
#fsdb account passwd uid gid fullname homedir shell
johnh * 2274 134 John_Heidemann /home/johnh /bin/bash
greg * 2275 134 Greg_Johnson /home/greg /bin/bash
root * 0 0 Root /root /bin/bash
# this is a simple database

Command:
cat DATA/passwd.fsdb | dbrow '_fullname =~ /John/'

Output:
#fsdb account passwd uid gid fullname homedir shell
johnh * 2274 134 John_Heidemann /home/johnh /bin/bash
greg * 2275 134 Greg_Johnson /home/greg /bin/bash
# this is a simple database
# | /home/johnh/BIN/DB/dbrow

BUGS

Doesn’t detect references to unknown columns in conditions.

END
#’ for font-lock mode.
exit 1;

CLASS FUNCTIONS

new
$filter = new Fsdb::Filter::dbrow(@arguments);

Create a new dbrow object, taking command-line arguments.

set_defaults
$filter->set_defaults();

Internal: set up defaults.

parse_options
$filter->parse_options(@ARGV);

Internal: parse command-line arguments.

setup
$filter->setup();

Internal: setup, parse headers.

run
$filter->run();

Internal: run over each rows.

AUTHOR and COPYRIGHT

Copyright (C) 1991-2018 by John Heidemann <johnh AT isi DOT edu>

This program is distributed under terms of the GNU general public license, version 2. See the file COPYING with the distribution for details.