oreilly.comSafari Books Online.Conferences.


Email.Email article link
Linux in a Nutshell (cover)

Alphabetical Directory of Linux Commands

This directory of Linux commands is from Linux in a Nutshell, 3rd Edition. Click on any of the 379 commands below to get a description and list of available options. All links in the command summaries point to the online version of the book on Safari Bookshelf.

Buy it now, or read it online on Safari Bookshelf.

makedbm [options] infile outfile

NFS/NIS command. Make NIS dbm file. makedbm takes infile and converts it to a pair of files in ndbm format, namely outfile.pag and outfile.dir. Each line of the input file is converted to a single dbm record. All characters up to the first TAB or SPACE form the key, and the rest of the line is the data. If line ends with \&, the data for that record is continued on to the next line. It is left for the NIS clients to interpret #; makedbm does not treat it as a comment character. infile can be -, in which case the standard input is read.

makedbm generates a special entry with the key yp_last_modified, which is the date of infile (or the current time, if infile is -).



Interdomain. Propagate a map to all servers using the interdomain name server named.

-d yp_domain_name

Create a special entry with the key yp_domain_name.

-i yp_input_file

Create a special entry with the key yp_input_file.


Convert keys of the given map to lowercase.

-m yp_master_name

Create a special entry with the key yp_master_name. If no master hostname is specified, yp_master_name is set to the local hostname.

-o yp_output_file

Create a special entry with the key yp_output_name.


Secure map. Accept connections from secure NIS networks only.

-u dbm filename

Undo a dbm file�print out a dbm file, one entry per line, with a single space separating keys from values.


It is easy to write shell scripts to convert standard files such as /etc/passwd to the key value form used by makedbm. For example, the awk program:

BEGIN { FS =":";OFS = "\t";}
{ print $1, $0}

takes the /etc/passwd file and converts it to a form that can be read by makdbm to make the NIS file passwd.byname. That is, the key is a username and the value is the remaining line in the /etc/passwd file.

Return to: Alphabetical Directory of Linux Commands

Linux Resources
  • Linux Online
  • The Linux FAQ
  • Linux Kernel Archives
  • Kernel Traffic

  • Sponsored by: