Name
text
Synopsis
The
text
database-map type allows you to look up keys
in flat text files. This technique is vastly less efficient than
looking up keys in real databases, but it can serve as a way to test
rules before implementing them in database form.
For the text
database map, columns for the key and
value are measured as an index. That is, the first column is number
0. To illustrate, consider the following mini-configuration file that
can be used to check spelling:
Kspell text /usr/dict/words Spell R$- $: $(spell $1 $: not in dictionary $)
The /usr/dict/words file contains only a single column of words. This rule shows that the key is (by default) the first column (index 0). And the value is (by default) also the first column (index 0).
For more sophisticated applications you can specify the
key’s column (with the -k
switch), the value’s column (with the
-v
switch), and the column delimiter (with the
-z
switch). To illustrate, consider the need to
look up a user-id in the
/etc/passwd file and to return the login name of
the user to whom it belongs:
Kgetuid text -k2 -v0 -z: /etc/passwd R$- $: $(getuid $1 $)
The lines of a password file look like this:
ftp:*:1092:255:File Transfer Protocol Program:/u/ftp:/bin/sh
The third column (where the columns are separated by colons) is the
uid field. The first is the login name. Note
that the -k
and -v
switches
show these fields as indexes, where the first is 0 and the third is
2.
Note that if a file cannot be opened because it is unsafe (
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