1DIALRULES(5F) DIALRULES(5F)
2
6 dialrules - HylaFAX dial string processing rules
7
9 A dial string specifies how to dial the telephone in order to reach a
10 destination facsimile machine, or similar device. This string is sup‐
11 plied by a user with each outgoing facsimile job. User-supplied dial
12 strings need to be processed in two ways by the HylaFAX server pro‐
13 cesses: to craft a canonical phone number for use in locating the
14 receiver's capabilities, and to process into a form suitable for send‐
15 ing to a modem. In addition client applications may need to process a
16 dial string to formulate an external form that does not include private
17 information such as a credit card access code. Phone number canonical‐
18 ization and dial string preparation are done according to dial string
19 processing rules that are located in a file specified in the server
20 configuration file; see the DialStringRules parameter in hylafax-con‐
21 fig(5F). The generation of an externalized form for a dial string is
22 done by rules that optionally appear in /etc/hylafax/dialrules on
23 client machines.
24 A dial string rules file is an ASCII file containing one or more rule
26 sets. A rule set defines a set of transformation rules that are
27 sequentially applied to a dial string. Each rule set is associated
28 with an identifier, with certain well-known identifiers being used by
29 the facsimile server or client application. Each transformation rule
30 is a regular expression and a replacement string; the regular expres‐
31 sion is repeatedly applied to a dial string and any matching substring
32 is replaced by the replacement string.
33 The syntax of a dial string rules file is as follows. Comments are
35 introduced with the ``!'' character and continue to the end of the cur‐
36 rent line. Identifiers are formed from a leading alphabetic and any
37 number of subsequent alpha-numeric characters. A rule set is of the
38 form:
39 Identifier := [
40 rule1
41 rule2
42 ...
43 ]
44 where rule1, rule2, and so on are transformation rules. Line breaks
45 are significant. The initial rule set definition line and the trailing
46 ``]'' must be on separate lines; and each transformation rule must also
47 be on a single line. Transformation rules are of the two forms:
48 regular-expression = replacement
49 regular-expression = \RuleName(replacement)
50 where regular-expression is a POSIX 1003.2 extended regular expression
51 and replacement is a string that is substituted in place of any portion
52 of the dial string that is matched by the regular-expression. White
53 space is significant in parsing transformation rules. If a regular
54 expression or replacement string has embedded white space in it, then
55 the white space needs to be escaped with a ``\'' character or the
56 entire string should be enclosed in quote (``"'') marks. Replacement
57 strings may reference the entire string matched by the regular expres‐
58 sion with the ``&'' character. Substrings matched with the ``(...)''
59 constructs may be referenced by using ``\n'' where n is a single
60 numeric digit between 1 and 9 that refers to the n-th matched sub‐
61 string; c.f. re_format(7), sed(1), etc.
62 If \RuleName(replacement) is used, then the dial rule set RuleName will
64 be recursively applied to the expanded replacement and the result used
65 as the replacement for the matched pattern before continuing to process
66 the transformation rules.
67 To simplify and parameterize the construction of rule sets, dial string
69 rules files may also include simple text-oriented variable definitions.
70 A line of the form:
71 foo=string
72 defines a variable named foo that has the value string. String values
73 with embedded whitespace must use the ``\'' character or be enclosed in
74 quote marks. Variables are interpolated into transformation rules by
75 referencing them as:
76 ${var}
77 Note that variable interpolation is done only once, at the time a
78 transformation rule is defined. This means that forward references are
79 not supported and that circular definitions will not cause loops. The
80 facsimile server automatically defines four variables to have the val‐
81 ues defined in its configuration file: AreaCode, CountryCode, LongDis‐
82 tancePrefix, and InternationalPrefix These variables are initialized
83 before parsing a dial string rules file; thus if they are defined in
84 the rules file then they will override any definition by the server.
85 There are three well known rule set names: CanonicalNumber to convert a
87 dial string to a canonical format, DialString to prepare a dial string
88 before using it to dial the telephone, and DisplayNumber to convert a
89 dial string to an external ``displayable'' form that does not include
90 the private information that might appear in the raw dial string.
91
93 This is the default set of rules for transforming a dial string into a
94 canonical phone number:
95 Area=${AreaCode} ! local area code
96 Country=${CountryCode} ! local country code
97 IDPrefix=${InternationalPrefix} ! prefix for placing an international call
98 LDPrefix=${LongDistancePrefix} ! prefix for placing a long distance call
99 !
100 ! Convert a phone number to a canonical format:
101 !
102 ! +<country><areacode><rest>
103 !
104 ! by (possibly) stripping off leading dialing prefixes for
105 ! long distance and/or international dialing.
106 !
107 CanonicalNumber := [
108 %.* = ! strip calling card stuff
109 [abcABC] = 2 ! these convert alpha to numbers
110 [defDEF] = 3
111 [ghiGHI] = 4
112 [jklJKL] = 5
113 [mnoMNO] = 6
114 [prsPRS] = 7
115 [tuvTUV] = 8
116 [wxyWXY] = 9
117 [^+0-9]+ = ! strip white space etc.
118 ^${IDPrefix} = + ! replace int. dialing code
119 ^${LDPrefix} = +${Country} ! replace l.d. dialing code
120 ^[^+] = +${Country}${Area}& ! otherwise, insert canon form
121 ]
122 The first rule simply strips anything following a ``%''; this will
123 remove any calling card-related information. The next eight rules con‐
124 vert upper and lower case alphabetics to the equivalent key numbers
125 (this is convenient for users that use mnemonic phone numbers). The
126 tenth rule removes everything but numbers and plus signs. The eleventh
127 rule translates any explicit international dialing prefix into the
128 ``+'' symbol used to identify country codes. The twelfth rule replaces
129 a leading long distance dialing prefix with the local country code
130 string. The last rule matches local phone numbers and inserts the
131 local country code and area code.
132 As an example, assume that
134 AreaCode=415
135 CountryCode=1
136 InternationalPrefix=011
137 LongDistancePrefix=1
138 then if the above set of rules is applied to ``01123965-Tube%2345'',
139 the transformations would be:
140 01123965-Tube%2345 01123965-Tube ! strip calling card stuff
141 01123965-Tube 01123965-8823 ! convert alphabetics
142 01123965-8823 011239658823 ! strip white space etc.
143 011239658823 +239658823 ! replace int. dialing code
144 +239658823 +239658823 ! replace l.d. dialing code
145 +239658823 +239658823 ! otherwise, insert canon form
146 for a final result of ``+239658823''.
147
149 sendfax(1), dialtest(8C), faxq(8C), faxsend(8C), faxgetty(8C), hylafax-
150 config(5F)
151 May 8, 1996 DIALRULES(5F)