Useful Tables

There are three useful tables in this chapter:

Table of LHS Operators

The LHS (lefthand side) of any rule is compared to the current contents of the workspace to determine whether the two match. Table 18-2 displays a variety of special operators offered by sendmail that make comparisons easier and more versatile.

Table 18-2. LHS operators

Operator

sendmail text reference

Description or use

$*

18.9.21[3ed]

Match zero or more tokens

$+

18.9.17[3ed]

Match one or more tokens

$-

18.9.16[3ed]

Match exactly one token

$@

18.9.2[3ed]

Match exactly zero tokens (V8 only)

$=

22.2.1[3ed]

Match any tokens in a class[a]

$~

22.2.2[3ed]

Match any single token not in a class

$#

18.9.18[3ed]

Match a literal $#

$|

18.9.23[3ed]

Match a literal $|

$&

21.5.3[3ed]

Delay macro expansion until runtime

[a] Class matches either a single token or multiple tokens, depending on the version of sendmail (§22.2[3ed]).

Table of RHS Operators

The RHS (right-hand side) of a rule rewrites the workspace. To make this rewriting more versatile, sendmail offers several special RHS operators. The complete list is shown in Table 18-3.

Table 18-3. RHS operators

RHS

sendmail text reference ...

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