Channel configuration strings

MMDF uses channel configuration strings to obtain detail information about the channel. Only the uucp and smtp channels utilize configuration strings.

Specify configuration strings, when adding or modifying a channel.

The uucp configuration string

The default uucp channel configuration string specifies the number of addresses a host can handle in a single mail command. The default value is 1. The syntax of the string is:

   naddrs=N

UUCP parameters include:

naddrs

the maximum number of addresses the uucp channel puts in a single uux(C) command. The default is 1 for backwards compatibility with older UUCP systems, which can process only one address at a time.

If you know that all sites with which you exchange mail via UUCP can handle more than one address, you can set naddrs to a higher value. Alternatively, you can create a second UUCP channel, with naddrs set to a larger value, for those UUCP sites that can handle more addresses.

maxlen

the maximum length of a uux command-line. The default value for maxlen is 1024. We recommend against raising the value of maxlen.

rewrite

controls how addresses are rewritten when being used as arguments to the rmail(ADM) command on a remote machine.

The possible values are:

rewrite=976	uses RFC 976 address format
rewrite=822	uses RFC 822 address format
rewrite=733	uses RFC 733 address format

The default value for rewrite is 976.

When using RFC 976 address format, addresses are rewritten as:

Address	Rewritten as
host1!host2!host3!user	host1!host2!host3!user
user%host3%host2@host1	host1!host2!host3!user
@host1,@host2:user@host3	host1!host2!host3!user

Simpler addresses, such as the most commonly-used user@host, are left alone except under RFC 976, where they are rewritten as host!user.

When using RFC 822 address format, addresses are rewritten as:

Address	Rewritten as
host1!host2!host3!user	host1!host2!host3!user
user%host3%host2@host1	user%host3%host2@host1
@host1,@host2:user@host3	@host1,@host2:user@host3

When using RFC 733 address format, addresses are rewritten as:

Address	Rewritten as
host1!host2!host3!user	host1!host2!host3!user
user%host3%host2@host1	user%host3%host2@host1
@host1,@host2:user@host3	user%host3%host2@host1

The smtp configuration string

The default smtp channel configuration string specifies the SMTP name of the host and the character set to be used. The syntax of the string is:

   hostname=hostname, charset=[7,8]bit

The value of charset specifies whether messages contain 7- or 8-bit data. Using the 8-bit setting violates the SMTP protocol standard specified by the Internet technical bulletin, RFC 821, (available from the InterNIC Registration Services, or InterNIC; see ``Registering domain names''). However, the 8-bit setting is widely used in Europe. The default value is 7-bit.