Plan B User's Manual


Name

intro ­ Introduction to System Boxes.

Synopsis

/b

Description

The name space of a Plan B application is made of a set of names that have boxes attached to them. This section describes the set of boxes that are expected to be available on a Plan B system. All of them are imported at prefixes starting with "/b", although some of them are also imported at conventional names like "/bin". The synopsis in each page shows the prefix for each system box along with the set of inner boxes supplied.

Depending on the exact configuration some of these boxes may not be available; nevertheless, those missing can be imported from other network locations.

Beware that once a system box is forgotten, there is no way to get back to it (unless it is also exported by the system to the network). This is not a problem since a new namespace starts with a standard set of system boxes imported to well-known prefixes.

Appart from the set of boxes supplied by the system, there is a set of conventions that are important for system operation. The conventions are changing quickly since Plan B is just born. Therefore, you should expect that most of the boxes shown in this section are likely to change as experience with the system is gained.

As of today, this is the typical hierarchy of boxes found in a name space:

/

bin
b
sys
proc
usr
mem
chan
term
fs
con
udp
tcp
doc
2
4
p95
bin
include
lib
p98
386
port
lib
font
proc
src
b
cmd
lib⋯
tmp
usr

Those under /b are boxes from the local kernel. All other ones are prefixes where some other boxes (including the local ones) may be mounted. For example, /bin is usually a set of imports from either local /b/fs/bin boxes or from network boxes advertised as /bin.

/bin   contains boxes with binary code ready to be executed on available processors.
/b     contains kernel-supplied boxes. For boxes under /b you can refer to the following manual pages to see what services are provided by each one.
/doc   contains system documentation. Inner boxes named /doc/2 and /doc/4 contain the sections 2 and 4 of the user's manual.
/p95   is the outter box for binaries, includes, and libraries dependent on the p95 architecture (Hosted on Plan 9 for ARM processors). It is expected to contain /p95/bin, /p95/include, and /p95/lib boxes. Following machine-dependent boxes have the same structure.
/p98   is the outter box for p98 boxes (Hosted on Plan 9 for 386 processors).
/386   is not used by now. The name is reserved for 386 depedent boxes that will be necessary after implementing a native version of the system for Intel based PCs.
/porthas the same structure of the machine-dependent boxes, but includes portable code that is expected to work on all architectures. Shell scripts go under /port/bin.
/proc
contains processor boxes used to start new programs.
/src   contains system source, both for kernel and user commands.
/tmp   is used to create temporary boxes. It is expected to be highly volatile.
/usr   is the outter box for user's boxes. User nemo uses /usr/nemo as his outter box. Beware that /b/usr serves a quite different purpose, since usr(4) is used to represent humans and not to contain user's boxes; i.e. /b/usr/nemo is the human known as Nemo to the system, as far as Plan B is concerned.

Announces

Some system boxes use to be announced to the network. This section describes which ones.

Source

/src/b

See also

Plan B: Boxes for network resources. Francisco J Ballesteros.

The Box: A replacement for files. Francisco J Ballesteros and Sergio Arevalo. HotOS-VII.

intro(1).

Bugs

Many, this section is not different and system boxes still have many bugs to fix.


Plan B User's Manual. First edition.