/****----  init create function  ----****/

int32 init_cr_<data-type>( int32 hdf_fp, int32 sd_id, int32 an_id, char *classname)

    purpose:
       Set up HDF file to handle writing of <data-type> records.  Must be 
       done before you can write any <data-type> records.

    return value: 
      -1 on error
       0 otherwise

    input values: 
       int32 hdf_fp - Generated with Hopen()
       int32 sd_id  - Generated with SDstart()
       int32 an_id  - Generated with ANstart()
       char *classname - User defined name to attach to the data type

/* Included for backwards compatibility */
int32 init_wr_<data-type>() : same as init_cr_<data-type>()


/******---- write function ----******/

int32 write_<data-type>(struct <data-type-struct> struct_name, int32 recnum)

    purpose: 
       write one record of <data-type> to HDF file.  Location in file 
       (record number) is specified by recnum.

    return value:
      -1 on error 
       0 otherwise
       
    input values:
	struct <data-type-struct> struct_name - C structure describing 
	   data record to be written to the HDF file.

	int32 recnum - record number you wish to write to.  Can be 
	   used to overwrite old records.  Using a -1 for this value 
	   will cause it to write to the record after the last one 
	   written in this run.  Will start at 0 if no previous record.


/*----   close write function    ----*/

void close_wr_<data-type>()

    purpose:
	shut down all HDF write access to <data-type>.  Use when done 
        writing data to <data-type>.

    return value : none
    input values : none


/*----     init access function    ----*/

int32 init_acc_<data-type>(int32 hdf_fp, int32 sd_id, char *access_mode)

    purpose:
       Set up HDF file to handle reading or overwriting of 
       <data-type> records.  Must be done before you can read 
       any <data-type> records.

    return value: 
       number of valid records of <data-type> in file.
       -1 on error 

    input values: 
       int32 hdf_fp - Generated with Hopen()
       int32 sd_id  - Generated with SDstart()
       char *access_mode - "r" for reading, "w" for writing


/* Included for backwards compatability */

int32 init_rd_<data-type>() : same as init_acc_<data-type>()
    

/******---- read function ----******/

int32 read_<data-type>(struct <data-type-struct> *struct_name, int32 recnum_rd)
      
    purpose: 
       read one record of <data-type> from HDF file.  Location in file 
       (record number) is specified by recnum_rd.

    return value:
      -1 on error or EOF
       0 otherwise
       
    input values:
	struct <data-type-struct> *struct_name - pointer to C structure 
	   where the record of <data-type> will we stored.

	int32 recnum_rd - record number you wish to read from. Using a -1 
	   for this value will cause it to read the record after the
	   last one read in this run.  Will start at 0 if no previous
	   record.


/*----   close read function    ----*/

void close_rd_<data-type>()
    purpose:
	shut down all HDF access to <data-type>.  Use when done 
        accessing data from <data-type>.

    return value : none
    input values : none


/*----  Get V group id, function    ----*/
int32 get_vgrp_id_<data-type>()

    purpose:
	pass the vgroup_id of <data-type>

    return value : vgroup_id 
    input values : none


/*----   V group description function    ----*/
int32 wr_Vgrp_desc_<data-type>(char *wr_strval)

    purpose:
	pass the vgroup description of <data-type>, which is the C 
	structure describing <data-type>.

    return value : 0

    input values : 
	*wr_strval - pointer to character array which will hold the 
	  description