PLUMBING(6) PLUMBING(6)
NAME
plumbing - plumbing rules
DESCRIPTION
Plumbing rules tell plumber(8) how to route plumbing mes-
sages generated by applications using plumbmsg(2).
The file is a set of rules separated by blank lines. Each
rule is a set of patterns followed by a set of actions. The
rules are interpreted in order. The first rule whose pat-
terns all match is applied, and no further rules are exam-
ined. Comments start with # and continue to end of line.
Single quotes protect special characters (use '' to get a
single quote).
A pattern has the general form:
field verb arg
Each field corresponds to a field in the incoming plumbing
message:
src Source application
dst Destination port
dir Working directory
kind Format of the data (eg, text or image)
attr A line of name=value pairs
data The message data (an array of bytes)
The verbs are:
is Exact string comparison with arg
matches Regular expression comparison with arg
isdir Arg must name an existing directory
isfile Arg must name an existing file
set Set the value of the field to arg. This verb
operates in place, so put it after all other
patterns in the rule.
The arg can refer to one of the following variables:
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PLUMBING(6) PLUMBING(6)
$0 to $9 Substrings resulting from the most recent
regular expression match: $0 is the entire
substring; $1 the first parenthesised sub-
string, etc.
$file The file name examined by the last isfile
verb.
$dir The directory name examined by the last
isdir verb.
The following actions are provided:
plumb to port
Route the message to the given plumbing port.
plumb start command arg ...
If no program is currently listening on the cur-
rent rule's port, start the command with the given
arguments. The `$' variables listed above can be
used, to include part of the message in the com-
mand line arguments to the program. They are
replaced in the command string by their actual
values.
For example, the following rule sends the names of module
files- file names ending with suffix `.m'- to wm-brutus(1),
starting it if it is not already running:
kind is text
data matches '([a-zA-Z0-9]+.m)(:[0-9]+)?'
data isfile /module/$1
data set /module/$0
plumb to edit
plumb start /dis/wm/brutus.dis $file$2
Note the use of $2 in the start action to pass brutus the
line number selected by the second parenthesised expression
in the pattern.
FILES
/usr/user/lib/plumbing
SEE ALSO
plumb(1), plumbmsg(2), plumber(8)
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