1Fsdb::Filter::dbrow(3)User Contributed Perl DocumentationFsdb::Filter::dbrow(3)
2
3
4
6 dbrow - select rows from an Fsdb file based on arbitrary conditions
7
9 dbrow [-vw] CONDITION [CONDITION...]
10
12 Select rows for which all CONDITIONS are true. Conditions are
13 specified as Perl code, in which column names are be embedded, preceded
14 by underscores.
15
17 -v Invert the selection, picking rows where at least one condition
18 does not match.
19
20 This module also supports the standard fsdb options:
21
22 -d Enable debugging output.
23
24 -w or --warnings
25 Enable warnings in user supplied code.
26
27 -i or --input InputSource
28 Read from InputSource, typically a file name, or "-" for standard
29 input, or (if in Perl) a IO::Handle, Fsdb::IO or Fsdb::BoundedQueue
30 objects.
31
32 -o or --output OutputDestination
33 Write to OutputDestination, typically a file name, or "-" for
34 standard output, or (if in Perl) a IO::Handle, Fsdb::IO or
35 Fsdb::BoundedQueue objects.
36
37 --autorun or --noautorun
38 By default, programs process automatically, but Fsdb::Filter
39 objects in Perl do not run until you invoke the run() method. The
40 "--(no)autorun" option controls that behavior within Perl.
41
42 --header H
43 Use H as the full Fsdb header, rather than reading a header from
44 then input.
45
46 --help
47 Show help.
48
49 --man
50 Show full manual.
51
53 Input:
54 #fsdb account passwd uid gid fullname homedir shell
55 johnh * 2274 134 John_Heidemann /home/johnh /bin/bash
56 greg * 2275 134 Greg_Johnson /home/greg /bin/bash
57 root * 0 0 Root /root /bin/bash
58 # this is a simple database
59
60 Command:
61 cat DATA/passwd.fsdb | dbrow '_fullname =~ /John/'
62
63 Output:
64 #fsdb account passwd uid gid fullname homedir shell
65 johnh * 2274 134 John_Heidemann /home/johnh /bin/bash
66 greg * 2275 134 Greg_Johnson /home/greg /bin/bash
67 # this is a simple database
68 # | /home/johnh/BIN/DB/dbrow
69
71 Doesn't detect references to unknown columns in conditions.
72
73 END
74 #' for font-lock mode.
75 exit 1;
76
78 new
79 $filter = new Fsdb::Filter::dbrow(@arguments);
80
81 Create a new dbrow object, taking command-line arguments.
82
83 set_defaults
84 $filter->set_defaults();
85
86 Internal: set up defaults.
87
88 parse_options
89 $filter->parse_options(@ARGV);
90
91 Internal: parse command-line arguments.
92
93 setup
94 $filter->setup();
95
96 Internal: setup, parse headers.
97
98 run
99 $filter->run();
100
101 Internal: run over each rows.
102
104 Copyright (C) 1991-2018 by John Heidemann <johnh@isi.edu>
105
106 This program is distributed under terms of the GNU general public
107 license, version 2. See the file COPYING with the distribution for
108 details.
109
110
111
112perl v5.32.0 2020-11-16 Fsdb::Filter::dbrow(3)