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+# @(#)README 8.1 (Berkeley) 6/4/93
+This package implements a superset of the hsearch and dbm/ndbm libraries.
+Test Programs:
+ All test programs which need key/data pairs expect them entered
+ with key and data on separate lines
+ tcreat3.c
+ Takes
+ bucketsize (bsize),
+ fill factor (ffactor), and
+ initial number of elements (nelem).
+ Creates a hash table named hashtest containing the
+ keys/data pairs entered from standard in.
+ thash4.c
+ Takes
+ bucketsize (bsize),
+ fill factor (ffactor),
+ initial number of elements (nelem)
+ bytes of cache (ncached), and
+ file from which to read data (fname)
+ Creates a table from the key/data pairs on standard in and
+ then does a read of each key/data in fname
+ tdel.c
+ Takes
+ bucketsize (bsize), and
+ fill factor (ffactor).
+ file from which to read data (fname)
+ Reads each key/data pair from fname and deletes the
+ key from the hash table hashtest
+ tseq.c
+ Reads the key/data pairs in the file hashtest and writes them
+ to standard out.
+ tread2.c
+ Takes
+ butes of cache (ncached).
+ Reads key/data pairs from standard in and looks them up
+ in the file hashtest.
+ tverify.c
+ Reads key/data pairs from standard in, looks them up
+ in the file hashtest, and verifies that the data is
+ correct.
+The file search.h is provided for using the hsearch compatible interface
+on BSD systems. On System V derived systems, search.h should appear in
+The man page ../man/db.3 explains the interface to the hashing system.
+The file hash.ps is a postscript copy of a paper explaining
+the history, implementation, and performance of the hash package.
+"bugs" or idiosyncracies
+If you have a lot of overflows, it is possible to run out of overflow
+pages. Currently, this will cause a message to be printed on stderr.
+Eventually, this will be indicated by a return error code.
+If you are using the ndbm interface and exit without flushing or closing the
+file, you may lose updates since the package buffers all writes. Also,
+the db interface only creates a single database file. To avoid overwriting
+the user's original file, the suffix ".db" is appended to the file name
+passed to dbm_open. Additionally, if your code "knows" about the historic
+.dir and .pag files, it will break.
+There is a fundamental difference between this package and the old hsearch.
+Hsearch requires the user to maintain the keys and data in the application's
+allocated memory while hash takes care of all storage management. The down
+side is that the byte strings passed in the ENTRY structure must be null
+terminated (both the keys and the data).