D. J. Bernstein
Data structures and program structures
cdb

The cdbget program

     cdbget k
cdbget searches for a record with key k in a constant database. The constant database must be readable (and seekable) on cdbget's standard input.

Normally cdbget prints the data in the first record with key k and exits 0. If there is no record with the key k, cdbget exits 100 without printing anything.

If cdbget encounters a read error, write error, or database format error, it complains and exits 111.

     cdbget k s
Given a numeric s argument, cdbget skips past the first s records with key k, and prints the data in the next record.