December 2002
Intermediate to advanced
1232 pages
56h 38m
English
Content preview from Sendmail, 3rd Edition
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Header Behavior in conf.c
The
sendmail program has a built-in understanding of
many header names. How those names are used is determined by a set of
flags in the source file conf.c supplied with
the source distribution. Site policy determines which flags are
applied to which headers, but in general, conf.c
applies them in the way that is best suited for almost all Internet
sites. If you desire to redefine the flags for a particular header
name, look for the name’s declaration in the
C-language structure definition HdrInfo in
conf.c. Be sure to read the comments in that
file. Changes to header flags represent a permanent site policy
change and should not be undertaken lightly. (We illustrate this
process after explaining the flags.)
The flags that determine header use are listed in Table 25-3. Note that each flag name is prefixed with an
H_.
Table 25-3. Header flags in conf.c
|
Flag |
§ |
Version |
Description |
|
H_ACHECK |
V5 and above |
Always process
| |
|
H_BCC |
V8.7 and above |
Strip value from header | |
|
H_BINDLATE |
V8.10 and above |
Expand macros only at time of delivery | |
|
H_CHECK |
V5 and above |
Process
| |
|
H_CTE |
V8.7 and above |
Is “content transfer encoding” | |
|
H_CTYPE |
V8.7 and above |
Is “content type” | |
|
H_DEFAULT |
V5 and above |
If already in headers, don’t insert | |
|
H_ENCODABLE |
V8.8 and above |
Field can be RFC2047-encoded | |
|
H_EOH |
V5 and ... |
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