DBM(3) BSD Library Functions Manual DBM(3)

NAME
     ddbbmmcclleeaarreerrrr, ddbbmmcclloossee, ddbbmmddeelleettee, ddbbmmddiirrffnnoo, ddbbmmeerrrroorr, ddbbmmffeettcchh,
     ddbbmmffiirrssttkkeeyy, ddbbmmnneexxttkkeeyy, ddbbmmooppeenn, ddbbmmssttoorree - database access func-
     tions

SYNOPSIS
     ##iinncclluuddee <>

     int
     ddbbmmcclleeaarreerrrr(DBM *db);

     void
     ddbbmmcclloossee(DBM *db);

     int
     ddbbmmddeelleettee(DBM *db, datum key);

     int
     ddbbmmddiirrffnnoo(DBM *db);

     int
     ddbbmmeerrrroorr(DBM *db);

     datum
     ddbbmmffeettcchh(DBM *db, datum key);

     datum
     ddbbmmffiirrssttkkeeyy(DBM *db);

     datum
     ddbbmmnneexxttkkeeyy(DBM *db);

     DBM *
     ddbbmmooppeenn(const char *file, int openflags, modet filemode);

     int
     ddbbmmssttoorree(DBM *db, datum key, datum content, int storemode);

DESCRIPTION
     Database access functions.  These functions are implemented using
     dbopen(3) with a hash(3) database.

     datum is declared in :

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

     The ddbbmmooppeenn(file, openflags, filemode) function opens or creates a
     database file.  The file argument is the basename of the file containing
     the database; the actual database has a .db suffix.  I.e., if file is
     "/home/me/mystuff" then the actual database is in the file
     /home/me/mystuff.db.  The openflags and filemode arguments are passed
     to open(2).  (ORDWR | OCREAT) is a typical value for openflags; 0660
     is a typical value for filemode.  OWRONLY is treated as ORDWR in
     openflags.  The pointer returned by ddbbmmooppeenn() identifies the database
     and is the db argument to the other functions.  The ddbbmmooppeenn() function
     returns NULL and sets errno if there were any errors.

     The ddbbmmcclloossee(db) function closes the database.  The ddbbmmcclloossee() function
     normally returns zero.

     The ddbbmmssttoorree(db, key, content, storemode) function inserts or replaces
     an entry in the database.  The storemode argument is either DBMINSERT
     or DBMREPLACE.  If storemode is DBMINSERT and the database already
     contains an entry for key, that entry is not replaced.  Otherwise the
     entry is replaced or inserted.  The ddbbmmssttoorree() function normally returns
     zero but returns 1 if the entry could not be inserted (because storemode
     is DBMINSERT, and an entry with key already exists) or returns -1 and
     sets errno if there were any errors.

     The ddbbmmffeettcchh(db, key) function returns NULL or the content corresponding
     to key.

     The ddbbmmddeelleettee(db, key) function deletes the entry for key.  The
     ddbbmmddeelleettee() function normally returns zero but returns 1 if there was no
     entry with key in the database or returns -1 and sets errno if there were
     any errors.

     The ddbbmmffiirrssttkkeeyy(db) function returns the first key in the database.  The
     ddbbmmnneexxttkkeeyy(db) function returns subsequent keys.  The ddbbffiirrssttkkeeyy()
     function must be called before ddbbmmnneexxttkkeeyy().  The order in which keys
     are returned is unspecified and may appear random.  The ddbbmmnneexxttkkeeyy()
     function returns NULL after all keys have been returned.

     The ddbbmmeerrrroorr(db) function returns the errno value of the most recent
     error.  The ddbbmmcclleeaarreerrrr(db) function resets this value to 0 and returns
     0.

     The ddbbmmddiirrffnnoo(db) function returns the file descriptor to the database.

LEGACY SYNOPSIS
     ##iinncclluuddee <>
     ##iinncclluuddee <>

     The include file  is necessary for all functions.

     DBM *
     ddbbmmooppeenn(const char *file, int openflags, int filemode);

     filemode has type int.

SEE ALSO
     open(2), dbopen(3), hash(3), compat(5)

STANDARDS     These functions (except ddbbmmddiirrffnnoo()) are included in the Version 2 of
     the Single UNIX Specification (``SUSv2'').

BSD                              July 7, 1999                              BSD