NAME

       gd_nframes — report the size of a dirfile

SYNOPSIS

       #include <getdata.h>

       off_t gd_nframes(DIRFILE *dirfile);

DESCRIPTION

       The  gd_nframes()  function queries a dirfile(5) database specified by dirfile and returns
       the number of frames in the database.  Since different fields may have differing number of
       frames,  the  Dirfile  Standards (see dirfile(5)) dictate that the number of frames in the
       database is defined to be equal to the number of frames in the reference field defined  by
       the  /REFERENCE  directive  (see  dirfile-format(5))  or,  if  no  such reference field is
       defined, by the first raw field specified in the format specification.

       If no vector fields are defined in the database, gd_nframes() returns zero and succeeds.

       The dirfile argument must point to a valid DIRFILE object previously created by a call  to
       gd_open(3).

RETURN VALUE

       Upon  successful completion, gd_nframes() returns the number of frames in the dirfile.  On
       error, it returns zero and sets the dirfile error to a  non-zero  error  value.   Possible
       error values are:

       GD_E_ALLOC
               The library was unable to allocate memory.

       GD_E_BAD_DIRFILE
               The supplied dirfile was invalid.

       GD_E_IO An  attempt to determine the (unencoded) size of the data file associated with the
               reference field failed.

       GD_E_UNKNOWN_ENCODING
               The size of the decoded data file associated with the reference field could not be
               not be determined because its encoding was not understood.

       GD_E_UNSUPPORTED
               The size of the decoded data file associated with the reference field could not be
               not be determined because its encoding was not supported.

       The dirfile error may be retrieved by calling gd_error(3).  A descriptive error string for
       the last error encountered can be obtained from a call to gd_error_string(3).

SEE ALSO

       dirfile(5),    dirfile-encoding(5),   gd_open(3),   gd_bof(3),   gd_eof(3),   gd_error(3),
       gd_error_string(3)