dbm(3)							     Library Functions Manual							    dbm(3)

NAME

       dbminit, fetch, store, delete, firstkey, nextkey, forder - Database subroutines

LIBRARY

       DBM Library (libdbm.a)

SYNOPSIS

       #include <dbm.h>

       typedef struct {
	   char *dptr;
	   int dsize; } datum;

       int dbminit(
	   char *file );

       datum fetch(
	   datum key );

       int store(
	   datum key,
	   datum content );

       int delete(
	   datum key );

       datum firstkey( void );

       datum nextkey(
	   datum key );

       long forder(
	   datum key );

PARAMETERS

       Specifies the database file.  Specifies the key.  Specifies a value associated with the key parameter.

DESCRIPTION

       The  dbminit(),	fetch(),  store(), delete(), firstkey(), nextkey(), and forder() functions maintain key/content pairs in a database.  They
       are obtained with the -ldbm loader option.  The dbm library is provided only for backwards compatibility, having been obsoleted by the ndbm
       functions in libc.  See the manual page for ndbm for more information.

       The  dbminit(),	fetch(),  store(),  delete(),  firstkey(),  nextkey(), and forder() functions handle very large databases (up to a billion
       blocks) and access a keyed item in one or two file system accesses.  Arbitrary binary data, as well as normal ASCII strings, are allowed.

       The database is stored in two files.  One file is a directory containing a bit map and has .dir as its suffix.  The  second  file  contains
       all data and has .pag as its suffix.

       Before  a  database  can  be accessed, it must be opened by the dbminit() function.  At the time that dbminit() is called, the file.dir and
       file.pag files must exist.  (An empty database is created by creating zero-length .dir and .pag files.)

       Once open, the data stored under a key is accessed by the fetch() function and data is placed under a key by the store() function.   A  key
       (and  its associated contents) is deleted by the delete() function.  A linear pass through all keys in a database may be made by use of the
       firstkey() and nextkey() functions.  The firstkey() function returns the first key in the database.  With any key, the  nextkey()  function
       returns	the  next  key	in  the  database.  The following code traverses the database: for (key = firstkey(); key.dptr != NULL; key = nex-
       tkey(key))

RETURN VALUES

       Upon successful completion, the functions that return an int return 0 (zero).  Otherwise, a negative number  is	returned.   The  functions
       that return a datum indicate errors with a null (0) dptr .

RELATED INFORMATION

       Functions: ndbm(3) delim off

																	    dbm(3)