The grib_handle

Typedefs
typedef struct grib_handle	grib_handle
Functions
int	grib_count_messages (grib_context *c, FILE *f, int *n)
	Counts the messages contained in a file resource.
grib_handle *	grib_handle_new_from_file (grib_context *c, FILE *f, int *error)
	Create a handle from a file resource.
grib_handle *	grib_handle_new_from_message (grib_context *c, void *data, size_t data_len)
	Create a handle from a user message.
grib_handle *	grib_handle_new_from_message_copy (grib_context *c, const void *data, size_t data_len)
	Create a handle from a user message.
grib_handle *	grib_handle_new_from_template (grib_context *c, const char *res_name)
	Create a handle from a read_only template resource.
grib_handle *	grib_handle_clone (grib_handle *h)
	Clone an existing handle using the context of the original handle, The message is copied and reparsed.
int	grib_handle_delete (grib_handle *h)
	Frees a handle, also frees the message if it is not a user message.

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Detailed Description

The grib_handle is the structure giving access to parsed grib values by keys.

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Typedef Documentation

typedef struct grib_handle grib_handle

Grib handle, structure giving access to parsed grib values by keys

Examples:

get.c, iterator.c, keys_iterator.c, multi.c, nearest.c, precision.c, print_data.c, and set.c.

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Function Documentation

int grib_count_messages	(	grib_context *	c,
		FILE *	f,
		int *	n
	)

Counts the messages contained in a file resource.

Parameters:

	c	: the context from wich the handle will be created (NULL for default context)
	f	: the file resource
	n	: the number of messages in the file

Returns:

0 if OK, integer value on error

grib_handle* grib_handle_clone

(

grib_handle *

h

)

Clone an existing handle using the context of the original handle, The message is copied and reparsed.

Parameters:

h

: The handle to be cloned

Returns:

the new handle, NULL if the message is invalid or a problem is encountered

int grib_handle_delete

(

grib_handle *

h

)

Frees a handle, also frees the message if it is not a user message.

See also:

grib_handle_new_from_message

Parameters:

h

: The handle to be deleted

Returns:

0 if OK, integer value on error

Examples:

get.c, iterator.c, multi.c, nearest.c, precision.c, print_data.c, and set.c.

grib_handle* grib_handle_new_from_file	(	grib_context *	c,
		FILE *	f,
		int *	error
	)

Create a handle from a file resource.

The file is read until a message is found. The message is then copied. Remember always to delete the handle when it is not needed any more to avoid memory leaks.

Parameters:

	c	: the context from wich the handle will be created (NULL for default context)
	f	: the file resource
	error	: error code set if the returned handle is NULL and the end of file is not reached

Returns:

the new handle, NULL if the resource is invalid or a problem is encountered

Examples:

get.c, iterator.c, keys_iterator.c, multi.c, precision.c, print_data.c, and set.c.

grib_handle* grib_handle_new_from_message	(	grib_context *	c,
		void *	data,
		size_t	data_len
	)

Create a handle from a user message.

The message will not be freed at the end. The message will be copied as soon as a modification is needed.

Parameters:

	c	: the context from which the handle will be created (NULL for default context)
	data	: the actual message
	data_len	: the length of the message in number of bytes

Returns:

the new handle, NULL if the message is invalid or a problem is encountered

grib_handle* grib_handle_new_from_message_copy	(	grib_context *	c,
		const void *	data,
		size_t	data_len
	)

Create a handle from a user message.

The message is copied and will be freed with the handle

Parameters:

	c	: the context from wich the handle will be created (NULL for default context)
	data	: the actual message
	data_len	: the length of the message in number of bytes

Returns:

the new handle, NULL if the message is invalid or a problem is encountered

grib_handle* grib_handle_new_from_template	(	grib_context *	c,
		const char *	res_name
	)

Create a handle from a read_only template resource.

The message is copied at the creation of the handle

Parameters:

	c	: the context from wich the handle will be created (NULL for default context)
	res_name	: the resource name

Returns:

the new handle, NULL if the resource is invalid or a problem is encountered

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