mkdbm -- Command

Build a data base for smail
/usr/lib/mail/mkdbm [-d] [-f] [-n] [-o output-file] [-v] [-y] [file ...]

The command mkdbm generates a data base for smail.

It forms the data key from the characters up to, but not including, a colon
(`:') or  white-space character.  The  data after the  colon or white-space
character forms  the value associated with  the key.  You can  use mkdbm to
produce data-base files  that can then be read by  a smail router pathalias
or  its  director  alias-file. By  default,  the  router  and director  are
configured  to  use  the DBM  file-access  protocol.   (For information  on
routers and directors, see the Lexicon entries for routers and directors.)

For some data  bases, you can use mkline to  form single-line records whose
comments  and  extra white  space  are removed.   The  generated data  base
contains a single NUL character at  the end of each key and value.  It also
generates a single  record that contains a `@' as  a key and value; it does
so for compatibility with the Berkeley sendmail command's alias files.

mkdbm recognizes the following command-line options:

-d Suppress writing the extra `@' record.

-f Fold the key to lower case before storing it within the data base.

-n Suppress writing a  NUL character at the end of  each line.  Please note
   that this  option is incompatible  with smail's method  of accessing the
   data-base file.

-o output-file
   Write output  into output-file. This  option also sets the  name for the
   data base.  If  you do not use this option,  mkdbm names the output data
   base after  its first file argument.  If, in  addition, the command line
   does not name an input file, mkmf names the output file dbm.

-v Write statistics to the standard output.

-y Create an output file that is  compatible with the Sun Yellow Pages (YP)
   system.  This obviates  the need for keeping a copy  of sendmail on your
   system to maintain a YP-alias data base.

If its command  line does not name an input  file, mkdbm reads the standard
input.  mkdbm also reads the standard input if a file is named `-'; in this
way, it can  mix data read from the standard  input with material read from
files.

Calling  mkdbm  with the  arguments  -ynd  generates a  data  base that  is
compatible  with  regular  YP  data  bases.   Using just  the  argument  -y
generates a data base that is compatible with the YP mail.alias data base.

As  it creates  the data  base, mkdbm  builds temporary  files in  the same
directory  in which  it eventually  builds the output  files.  When  it has
completed its work, mkdbm removes  all data-base files that have the target
name, sleeps for one or two seconds, then moves the newly written temporary
data-base files to the target names.  This method of writing a data-base is
not compatible with the locking method used by Berkeley command sendmail.

Example

As  an example  of the  use  of mkdbm  consider a  file named  paths, which
contains the routing information:

    .COM sun!%s
    Stargate.COM ames!cmcl2!uiucdcs!stargate!%s
    ames ames!%s
    .ATT.COM mtune!%s
    mtune mtune!%s

Given this file, the command

    mkdbm -f paths

produces a data base in the files paths.pag and paths.dir that contains the
above entries but with the keys  shifted into lower case.  For example, one
entry will contain the key stargate.com with an associated value of:

    ames!cmcl2!uiucdcs!stargate!%s

Files

dbmXXXXXX.pag
dbmXXXXXX.dir
     Temporary files, created in the same directory as the output files.

See Also

commands,
libgdbm,
mail [overview],
mkline,
pathalias,
smail

Notes

Copyright © 1987, 1988 Ronald S. Karr and Landon Curt Noll.  Copyright
© 1992 Ronald S. Karr.

mkdbm is  part of the smail  package.  For a full  copyright statement, see
file COPYING,  which is included with  source code to smail,  or type smail
-bc to  see the distribution  rights and restrictions  associated with this
software.

© 2012 by Stephen A. Ness