1Fsdb::Filter::dbrow(3)User Contributed Perl DocumentationFsdb::Filter::dbrow(3)
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6 dbrow - select rows from an Fsdb file based on arbitrary conditions
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9 dbrow [-vw] CONDITION [CONDITION...]
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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.
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17 -v Invert the selection, picking rows where at least one condition
18 does not match.
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20 This module also supports the standard fsdb options:
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22 -d Enable debugging output.
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24 -w or --warnings
25 Enable warnings in user supplied code.
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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.
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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.
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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.
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42 --header H
43 Use H as the full Fsdb header, rather than reading a header from
44 then input.
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46 --help
47 Show help.
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49 --man
50 Show full manual.
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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
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60 Command:
61 cat DATA/passwd.fsdb | dbrow '_fullname =~ /John/'
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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
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71 Doesn't detect references to unknown columns in conditions.
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73 END
74 #' for font-lock mode.
75 exit 1;
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78 new
79 $filter = new Fsdb::Filter::dbrow(@arguments);
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81 Create a new dbrow object, taking command-line arguments.
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83 set_defaults
84 $filter->set_defaults();
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86 Internal: set up defaults.
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88 parse_options
89 $filter->parse_options(@ARGV);
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91 Internal: parse command-line arguments.
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93 setup
94 $filter->setup();
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96 Internal: setup, parse headers.
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98 run
99 $filter->run();
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101 Internal: run over each rows.
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104 Copyright (C) 1991-2018 by John Heidemann <johnh@isi.edu>
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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.
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112perl v5.32.1 2021-01-27 Fsdb::Filter::dbrow(3)