Lines that contain no characters (empty lines)
are also ignored. Whitespace (spaces or tabs) separates the key on the left from the
data on the right.
The following is an example of such an input file:
key data
?†“ ?†“
lady relaysite!lady
my.host relaysite!lady
bug bug localuucp
The second line shows that keys can be multitokened (my.host is three tokens), but
cannot contain space or tab characters. The data is separated from the keys by one or
more space or tab characters. The last line shows that the data can contain internal
space and tab characters.
* Whenever you update to a newer version of sendmail, always update the version of the makemap program
in parallel. Old or vendor versions might not interoperate well with an updated sendmail.
This is the Title of the Book, eMatter Edition
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10.5 The makemap Program | 371
In reading from existing files, some conversion might be required to massage the
input into a usable form. To make a database of the /etc/hosts file (for converting
hostnames into IP addresses), for example, you might use a command line such as
the following:
% awk '/^[^#]/ {print $2, $1}' /etc/hosts | makemap ...
Here, awk(1) first eliminates the comment lines (the /^[^#]/). If it doesn??™t, it will
wrongly move them to the second column, where makemap will not recognize them
as comments.
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