g2_info.c File Reference

Search through a GRIB2 message and returns the number of gridded fields found in the message and the number (and maximum size) of Local Use Sections. More...

#include <stdio.h>
#include <stdlib.h>
#include "grib2.h"

Go to the source code of this file.

Functions
g2int	g2_info (unsigned char *cgrib, g2int *listsec0, g2int *listsec1, g2int *numfields, g2int *numlocal)
	This subroutine searches through a GRIB2 message and returns the number of gridded fields found in the message and the number (and maximum size) of Local Use Sections. More...

Detailed Description

Search through a GRIB2 message and returns the number of gridded fields found in the message and the number (and maximum size) of Local Use Sections.

Author

Stephen Gilbeert

Date

2002-10-28

Definition in file g2_info.c.

Function Documentation

g2_info()

g2int g2_info	(	unsigned char *	cgrib,
		g2int *	listsec0,
		g2int *	listsec1,
		g2int *	numfields,
		g2int *	numlocal
	)

This subroutine searches through a GRIB2 message and returns the number of gridded fields found in the message and the number (and maximum size) of Local Use Sections.

Also various checks are performed to see if the message is a valid GRIB2 message.

Parameters

cgrib	Character pointer to the GRIB2 message.
listsec0	pointer to an array containing information decoded from GRIB Indicator Section 0. Must be allocated with >= 3 elements. listsec0(0) Discipline-GRIB Master Table Number (Code Table 0.0). listsec0[1] GRIB Edition Number (currently 2). listsec0[2] Length of GRIB message.
listsec1	Pointer to an array containing information read from GRIB Identification Section 1. Must be allocated with >= 13 elements. listsec1[0] Id of orginating centre (Table 0). listsec1[1] Id of orginating sub-centre (Table C). listsec1[2] GRIB Master Tables Version Number (Table 1.0). listsec1[3] GRIB Local Tables Version Number (Table 1.1). listsec1[4] Significance of Reference Time (Table 1.2) listsec1[5] Reference Time - Year (4 digits) listsec1[6] Reference Time - Month listsec1[7] Reference Time - Day listsec1[8] Reference Time - Hour listsec1[9] Reference Time - Minute listsec1[10] Reference Time - Second listsec1[11] Production status of data (Table 1.3). listsec1[12] Type of processed data (Table 1.4).
numfields	The number of gridded fields found in the GRIB message. That is, the number of occurences of Sections 4 - 7.
numlocal	The number of Local Use Sections ( Section 2 ) found in the GRIB message.

Returns

0 foe success, otherwise:

• 1 Beginning characters "GRIB" not found.
• 2 GRIB message is not Edition 2.
• 3 Could not find Section 1, where expected.
• 4 End string "7777" found, but not where expected.
• 5 End string "7777" not found at end of message.
• 6 Invalid section number found.

Author

Stephen Gilbeert

Date

2002-10-28

Definition at line 67 of file g2_info.c.

References gbit().