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=head1 NAME
cdbmake -- create a constant database from scratch
=head1 SYNOPSIS
cdbmake F<database> F<tempfile>
=head1 DESCRIPTION
B<cdbmake> creates a new constant database from data read from its
standard input. Constant databases are portable between different
architectures.
=head2 Input Format
On its input, B<cdbmake> reads a series of records of format
+I<keylen>,I<valuelen>:I<key>-E<gt>I<value>
For example,
+3,9:foo->bar'n'baz
is a valid record. Each record is followed by a newline. The end of
records is indicated by and extra newline.
Keys and values can be binary data, and contain any characters.
=head2 Replacement Procedure
B<cdbmake> reads the data and writes to temporary file F<tempfile>,
syncinc the writes when done. It then atomically moves F<tempfile> to
F<database>. This ensures database reading needs no locking.
Files F<tempfile> and F<database> must reside on the same filesystem,
and the directories containing them must be writable to the user
invoking B<cdbmake>.
Do not run two simultaneous B<cdbmake>s with the same F<tempfile>.
=head2 Memory Usage
B<cdbmake> needs roughly 16 bytes of memory per record. Maximum
database size is 4 gigabytes.
=head1 RETURN VALUES
0 on success, 1 on syntax errors and 111 on transient errors.
=head1 RESTRICTIONS
Identical keys are allowed and stored, but not all readers support
them.
=head1 SEE ALSO
L<cdbdump(1)|cdbdump(1)>, L<cdbget(1)|cdbget(1)>, L<cdbstats(1)|cdbstats(1)>
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