#include "btree.h"
int btsel(BTA* btact, char* key, char* data, int dsize, int* rsize);
The btsel function locates and returns
the data record of an existing key in the file associated with
the btact context pointer. Both
key and data are
character pointers. The dsize
parameter must contain the maximum number of bytes to be
returned. The caller should ensure that the
data pointer refers to an area of
memory of at least dsize bytes. The
actual number of bytes returned is returned in
rsize. Even if the data record
contains more than dsize bytes, only
dsize bytes will be returned. If the
data record is successfully retrieved (even partially),
btsel returns zero.
An application program can determine the number of bytes in a
data record through the btrecs
function.
A non-zero return from btsel indicates an
error occurred.