Distrib Distributes Files?

What Does Distrib Do?

As we have seen, distrib:

• Selects machines (lines in a configuration file). The configuration file is the first of these that exists:
  • The file specified by the -C option. If its name ends in ".mcf", it is first processed by m4.
  • distrib.mcf in the current directory- after it's run through m4
  • distrib.cf in the current directory
  • distrib.mcf in distrib's library path (run it -V to see where that is- it's compiled in)- after it's run through m4
  • distrib.cf in distrib's library path (run it -V to see where that is- it's compiled in)
  • If you don't have one, it won't work, but there should be one installed in the library directory.
• The machines selected are either the default set (or a modification thereof) or the machines specified.
  • If -a is given, the set is all the machines and could be further modified (anded) by other options, but it's redundant in those cases.
  • If -m is given, only the specified machine is selected by HOST.
  • If -t is given, only machines with HOSTTYPE of one of the specified types are selected. This set can be modified by other options (-S, -G, explicit list of HOSTs).
  • If none of the above options or -S or a list of HOSTs is given, the default set is selected. The default set is all the machines having HOSTTYPE the same as MYTYPE (which is compiled in to distrib and can be seen with -V), except for the current machine (the one that distrib is running on). This set can only be modified by -I which also includes the current machine.
  • By itself, -S specifies all the machines that have HASSRC defined. It can modify other sets as well as be modified by other modifiers (-t, -G, explicit list of HOSTs).
  • Modifiable sets can be modified with arbitrary m4 code by use of the -G option. By itself, it specifies all machines that match the m4 code. (It doesn't use the default set, even if -I is specified.)
  • A list of HOSTs can be given. This can be modified as well (though distrib will whine about it).
• For each selected machine:
  • Macros are set. These come from:
    • The -D option to distrib
    • Any macros set by an assignment that are in effect for that line
    • Any items in columns on the selected line (machine)
  • With these macros set, m4 (M4_PATH from the environment or the compiled in path) is run on the Distfile. That Distfile is used for all the selected machines and is the first of:
    • A degenerate file containing just "HOST" if you give distrib the -H option.
    • The command line as a Distfile if the -c option is given. This is similar to the behavior of rdist. If only one argument is given, "HOST" is added. A special line can be added with distrib's -s option.
    • The file specified by distrib's -f option. This could be "-" for stdin
    • "Distfile" in the current directory
    • "distfile" in the current directory
    • If those aren't found, you'll get an error
  • If distrib thinks the Distfile is really an rdist Distfile because of its name being "Distfile" or "distfile", or because -c or -F was given, any files with names quoted by '@' are run through m4 with the same macros used for the Distfile. These processed files are stored in /tmp and their names are used in the Distfile in place of the original files' names. The processed files are made with the same modes as the originals so rdist will do the right thing.
  • Then distrib takes an action:
    • Prints the processed Distfile to stdout if -E is given.
    • Otherwise, it runs RDIST_PATH from the currently defined macros, or the environment, if it's set either place, else it runs rdist from the compiled-in location. The options passed to this program are mostly the remaining options of distrib and the right stuff to make it use the correct Distfile (from stdin or the command line).
  • Finally, distrib cleans up any temporary files it made.