dbcol (1) Linux Manual Page
NAME
dbcol – select columns from an Fsdb file
SYNOPSIS
dbcol [-v] [-e -] [column…]
DESCRIPTION
Select one or more columns from the input database. If a value is given for empty columns with the -e option, then any named columns which don’t exist will be created. Otherwise, non-existent columns are an error.
Note: a safer way to create columns is dbcolcreate.
OPTIONS
-ror–relaxed-errors- Relaxed error checking: ignore columns that aren’t there.
-vor–invert-match- Output all columns except those listed (like grep -v).
-eEmptyValue or–empty- Specify the value newly created columns get.
and the standard fsdb options:
-d- Enable debugging output.
-ior–inputInputSource- Read from InputSource, typically a file, or – for standard input, or (if in Perl) a IO::Handle, Fsdb::IO or Fsdb::BoundedQueue objects.
-oor–outputOutputDestination- Write to OutputDestination, typically a file, or – for standard output, or (if in Perl) a IO::Handle, Fsdb::IO or Fsdb::BoundedQueue objects.
–autorunor–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.
–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 account | dbcol account
Output:
#fsdb account
johnh
greg
root
# this is a simple database
# | dbcol account
SEE ALSO
dbcolcreate(1), Fsdb(3)
AUTHOR and COPYRIGHT
Copyright (C) 1991-2015 by John Heidemann <johnh [at] isi.edu>
This program is distributed under terms of the GNU general public license, version 2. See the file COPYING with the distribution for details.
