The grib_handle

Typedefs
typedef struct grib_handle	grib_handle
typedef struct grib_multi_handle	grib_multi_handle
Functions
int	grib_count_in_file (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 in memory.
grib_handle *	grib_handle_new_from_multi_message (grib_context *c, void **data, size_t *data_len, int *error)
	Create a handle from a user message in memory.
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_new_from_samples (grib_context *c, const char *res_name)
	Create a handle from a message contained in a samples directory.
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.
grib_multi_handle *	grib_multi_handle_new (grib_context *c)
	Create an empty multi field handle.
int	grib_multi_handle_append (grib_handle *h, int start_section, grib_multi_handle *mh)
	Append the sections starting with start_section of the message pointed by h at the end of the multi field handle mh.
int	grib_multi_handle_delete (grib_multi_handle *mh)
	Delete multi field handle.
int	grib_multi_handle_write (grib_multi_handle *mh, FILE *f)
	Write a multi field handle in a file.

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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, multi_write.c, nearest.c, precision.c, print_data.c, and set.c.

typedef struct grib_multi_handle grib_multi_handle

Grib multi field handle, structure used to build multi fields messages.

Examples:

multi_write.c.

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Function Documentation

int grib_count_in_file	(	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

Examples:

count_messages.f90.

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, multi_write.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, multi_write.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 in memory.

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_multi_message	(	grib_context *	c,
		void **	data,
		size_t *	data_len,
		int *	error
	)

Create a handle from a user message in memory.

The message will not be freed at the end. The message will be copied as soon as a modification is needed. This function works also with multi field messages.

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
	error	: error code

Returns:

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

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

Create a handle from a message contained in a samples directory.

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

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

int grib_multi_handle_append	(	grib_handle *	h,
		int	start_section,
		grib_multi_handle *	mh
	)

Append the sections starting with start_section of the message pointed by h at the end of the multi field handle mh.

Remember always to delete the multi handle when it is not needed any more to avoid memory leaks.

Parameters:

	h	: The handle from which the sections are copied.
	start_section	: section number. Starting from this section all the sections to then end of the message will be copied.
	mh	: The multi field handle on which the sections are appended.

Returns:

0 if OK, integer value on error

Examples:

multi_write.c.

int grib_multi_handle_delete

(

grib_multi_handle *

mh

)

Delete multi field handle.

Parameters:

mh

: The multi field handle to be deleted.

Returns:

0 if OK, integer value on error

Examples:

multi_write.c.

grib_multi_handle* grib_multi_handle_new

(

grib_context *

c

)

Create an empty multi field handle.

Remember always to delete the multi 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)

Examples:

multi_write.c.

int grib_multi_handle_write	(	grib_multi_handle *	mh,
		FILE *	f
	)

Write a multi field handle in a file.

Remember always to delete the multi handle when it is not needed any more to avoid memory leaks.

Parameters:

	mh	: The multi field handle to be written.
	f	: File on which the file handle is written.

Returns:

0 if OK, integer value on error

Examples:

multi_write.c.

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