NAME

       gd_spf — returns the samples per frame for a field in a dirfile

SYNOPSIS

       #include <getdata.h>

       unsigned int gd_spf(DIRFILE *dirfile, const char *field_code);

DESCRIPTION

       The  gd_spf()  function  queries a dirfile(5) database specified by dirfile and determines
       the number of samples per frame for  the  field  field_code.   This  information  is  also
       available from gd_entry(3).

       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_spf() returns a positive integer indicating the  number  of
       samples  per  frame  for  the  field  specified.   On  error, it returns zero and stores a
       negative-valued error code in the DIRFILE object which may be retrieved  by  a  subsequent
       call to gd_error(3).  Possible error codes are:

       GD_E_BAD_CODE
               The field specified by field_code was not found in the database.

       GD_E_BAD_DIRFILE
               The supplied dirfile was invalid.

       GD_E_DIMENSION
               A scalar field was found where a vector field was expected.

       GD_E_INTERNAL_ERROR
               An  internal error occurred in the library while trying to perform the task.  This
               indicates a bug in the library.  Please report the incident to the maintainer.

       GD_E_RECURSE_LEVEL
               Too many levels of recursion were encountered while trying to resolve  field_code.
               This  usually  indicates  a  circular  dependency  in  field  specification in the
               dirfile.

       A descriptive error string for the error may be obtained by calling gd_error_string(3).

HISTORY

       The get_spf() function appeared in GetData-0.3.0.

       In GetData-0.7.0, this function was renamed to gd_spf().

       In GetData-0.10.0, the error return from this function changed  from  -1  to  a  negative-
       valued error code.

SEE ALSO

       gd_entry(3), gd_error(3), gd_error_string(3), gd_open(3), dirfile(5)