dfile.c File Reference

File create and open functions. More...

#include "config.h"
#include <stdlib.h>
#include "ncdispatch.h"
#include "netcdf_mem.h"
#include "ncpathmgr.h"
#include "fbits.h"

Go to the source code of this file.

Functions
static int	check_create_mode (int mode)
	Check the create mode parameter for sanity.
int	nc__create (const char *path, int cmode, size_t initialsz, size_t *chunksizehintp, int *ncidp)
	Create a netCDF file with some extra parameters controlling classic file caching.
int	nc__create_mp (const char *path, int cmode, size_t initialsz, int basepe, size_t *chunksizehintp, int *ncidp)
int	nc__enddef (int ncid, size_t h_minfree, size_t v_align, size_t v_minfree, size_t r_align)
	Leave define mode with performance tuning.
int	nc__open (const char *path, int omode, size_t *chunksizehintp, int *ncidp)
	Open a netCDF file with extra performance parameters for the classic library.
int	nc__open_mp (const char *path, int omode, int basepe, size_t *chunksizehintp, int *ncidp)
int	nc__pseudofd (void)
int	nc_abort (int ncid)
	No longer necessary for user to invoke manually.
int	nc_close (int ncid)
	Close an open netCDF dataset.
int	nc_close_memio (int ncid, NC_memio *memio)
	Do a normal close (see nc_close()) on an in-memory dataset, then return a copy of the final memory contents of the dataset.
int	NC_create (const char *path0, int cmode, size_t initialsz, int basepe, size_t *chunksizehintp, int useparallel, void *parameters, int *ncidp)
int	nc_create (const char *path, int cmode, int *ncidp)
	Create a new netCDF file.
int	nc_create_mem (const char *path, int mode, size_t initialsize, int *ncidp)
	Create a netCDF file with the contents stored in memory.
int	nc_def_user_format (int mode_flag, NC_Dispatch *dispatch_table, char *magic_number)
	Add handling of user-defined format.
int	nc_enddef (int ncid)
	Leave define mode.
int	nc_inq (int ncid, int *ndimsp, int *nvarsp, int *nattsp, int *unlimdimidp)
	Inquire about a file or group.
int	nc_inq_base_pe (int ncid, int *pe)
int	nc_inq_format (int ncid, int *formatp)
	Inquire about the binary format of a netCDF file as presented by the API.
int	nc_inq_format_extended (int ncid, int *formatp, int *modep)
	Obtain more detailed (vis-a-vis nc_inq_format) format information about an open dataset.
int	nc_inq_nvars (int ncid, int *nvarsp)
	Learn the number of variables in a file or group.
int	nc_inq_path (int ncid, size_t *pathlen, char *path)
	Get the file pathname (or the opendap URL) which was used to open/create the ncid's file.
int	nc_inq_type (int ncid, nc_type xtype, char *name, size_t *size)
	Inquire about a type.
int	nc_inq_user_format (int mode_flag, NC_Dispatch **dispatch_table, char *magic_number)
	Inquire about user-defined format.
int	NC_open (const char *path0, int omode, int basepe, size_t *chunksizehintp, int useparallel, void *parameters, int *ncidp)
int	nc_open (const char *path, int omode, int *ncidp)
	Open an existing netCDF file.
int	nc_open_mem (const char *path, int omode, size_t size, void *memory, int *ncidp)
	Open a netCDF file with the contents taken from a block of memory.
int	nc_open_memio (const char *path, int omode, NC_memio *params, int *ncidp)
	Open a netCDF file with the contents taken from a block of memory.
int	nc_redef (int ncid)
	Put open netcdf dataset into define mode.
int	nc_set_base_pe (int ncid, int pe)
int	nc_set_fill (int ncid, int fillmode, int *old_modep)
	Change the fill-value mode to improve write performance.
int	nc_sync (int ncid)
	Synchronize an open netcdf dataset to disk.

Variables
int	NC_initialized
	True when dispatch table is initialized.
static int	pseudofd = 0
NC_Dispatch *	UDF0_dispatch_table = NULL
char	UDF0_magic_number [NC_MAX_MAGIC_NUMBER_LEN+1] = ""
NC_Dispatch *	UDF1_dispatch_table = NULL
char	UDF1_magic_number [NC_MAX_MAGIC_NUMBER_LEN+1] = ""

Detailed Description

File create and open functions.

These functions end up calling functions in one of the dispatch layers (netCDF-4, dap server, etc).

Copyright 2018 University Corporation for Atmospheric Research/Unidata. See COPYRIGHT file for more info.

Definition in file dfile.c.

Function Documentation

check_create_mode()

static int check_create_mode ( int mode )

static

Check the create mode parameter for sanity.

Some create flags cannot be used if corresponding library features are enabled during the build. This function does a pre-check of the mode flag before calling the dispatch layer nc_create functions.

Parameters

mode	The creation mode flag.

Returns

NC_NOERR No error.

NC_ENOTBUILT Requested feature not built into library

NC_EINVAL Invalid combination of modes.

Author

Ed Hartnett

Definition at line 1759 of file dfile.c.

nc__create_mp()

int nc__create_mp	(	const char *	path,
		int	cmode,
		size_t	initialsz,
		int	basepe,
		size_t *	chunksizehintp,
		int *	ncidp )

Create a file with special (deprecated) Cray settings.

Deprecated

This function was used in the old days with the Cray at NCAR. The Cray is long gone, and this call is supported only for backward compatibility. Use nc_create() instead.

Parameters

path	File name.
cmode	Create mode.
initialsz	Initial size of metadata region for classic files, ignored for other files.
basepe	Deprecated parameter from the Cray days.
chunksizehintp	A pointer to the chunk size hint. This only applies to classic files.
ncidp	Pointer that gets ncid.

Returns

NC_NOERR No error.

Author

Glenn Davis

Definition at line 534 of file dfile.c.

nc__open_mp()

int nc__open_mp	(	const char *	path,
		int	omode,
		int	basepe,
		size_t *	chunksizehintp,
		int *	ncidp )

Open a netCDF file with extra parameters for Cray.

Deprecated

This function was used in the old days with the Cray at NCAR. The Cray is long gone, and this call is supported only for backward compatibility. Use nc_open() instead.

Parameters

path	The file name of the new netCDF dataset.
omode	Open mode.
basepe	Deprecated parameter from the Cray days.
chunksizehintp	A pointer to the chunk size hint. This only applies to classic files.
ncidp	Pointer to location where returned netCDF ID is to be stored.

Returns

NC_NOERR

Author

Glenn Davis

Definition at line 865 of file dfile.c.

nc__pseudofd()

int nc__pseudofd

(

void

)

Create a pseudo file descriptor that does not overlap real file descriptors

Returns

pseudo file number

Author

Dennis Heimbigner

Definition at line 2158 of file dfile.c.

NC_create()

int NC_create	(	const char *	path0,
		int	cmode,
		size_t	initialsz,
		int	basepe,
		size_t *	chunksizehintp,
		int	useparallel,
		void *	parameters,
		int *	ncidp )

Create a file, calling the appropriate dispatch create call.

For create, we have the following pieces of information to use to determine the dispatch table:

• path
• cmode

Parameters

path0	The file name of the new netCDF dataset.
cmode	The creation mode flag, the same as in nc_create().
initialsz	This parameter sets the initial size of the file at creation time. This only applies to classic files.
basepe	Deprecated parameter from the Cray days.
chunksizehintp	A pointer to the chunk size hint. This only applies to classic files.
useparallel	Non-zero if parallel I/O is to be used on this file.
parameters	Pointer to MPI comm and info.
ncidp	Pointer to location where returned netCDF ID is to be stored.

Returns

NC_NOERR No error.

Author

Dennis Heimbigner, Ed Hartnett, Ward Fisher

Definition at line 1824 of file dfile.c.

nc_inq_base_pe()

int nc_inq_base_pe	(	int	ncid,
		int *	pe )

Learn base PE.

Deprecated

This function was used in the old days with the Cray at NCAR. The Cray is long gone, and this call is now meaningless. The value returned for pe is always 0.

Parameters

ncid	File and group ID.
pe	Pointer for base PE.

Returns

NC_NOERR No error.

NC_EBADID Invalid ncid passed.

Author

Glenn Davis

Definition at line 1488 of file dfile.c.

nc_inq_nvars()

int nc_inq_nvars	(	int	ncid,
		int *	nvarsp )

Learn the number of variables in a file or group.

Parameters

ncid	File and group ID.
nvarsp	Pointer that gets number of variables. Ignored if NULL.

Returns

NC_NOERR No error.

NC_EBADID Bad ncid.

Author

Glenn Davis, Ed Hartnett, Dennis Heimbigner

Definition at line 1645 of file dfile.c.

NC_open()

int NC_open	(	const char *	path0,
		int	omode,
		int	basepe,
		size_t *	chunksizehintp,
		int	useparallel,
		void *	parameters,
		int *	ncidp )

Open a netCDF file (or remote dataset) calling the appropriate dispatch function.

For open, we have the following pieces of information to use to determine the dispatch table.

• table specified by override
• path
• omode
• the contents of the file (if it exists), basically checking its magic number.

Parameters

path0	Path to the file to open.
omode	Open mode.
basepe	Base processing element (ignored).
chunksizehintp	Size hint for classic files.
useparallel	If true use parallel I/O.
parameters	Extra parameters for the open.
ncidp	Pointer that gets ncid.

Returns

NC_NOERR No error.

Author

Dennis Heimbigner

Definition at line 1962 of file dfile.c.

nc_set_base_pe()

int nc_set_base_pe	(	int	ncid,
		int	pe )

Sets base processing element (ignored).

Deprecated

This function was used in the old days with the Cray at NCAR. The Cray is long gone, and this call is supported only for backward compatibility.

Parameters

ncid	File ID.
pe	Base PE.

Returns

NC_NOERR No error.

NC_EBADID Invalid ncid passed.

Author

Glenn Davis

Definition at line 1512 of file dfile.c.

Variable Documentation

NC_initialized

int NC_initialized

extern

True when dispatch table is initialized.

pseudofd

int pseudofd = 0

static

Static counter for pseudo file descriptors (incremented)

Definition at line 2148 of file dfile.c.

UDF0_dispatch_table

NC_Dispatch* UDF0_dispatch_table = NULL

Definition at line 46 of file dfile.c.

UDF0_magic_number

char UDF0_magic_number[NC_MAX_MAGIC_NUMBER_LEN+1] = ""

Definition at line 47 of file dfile.c.

UDF1_dispatch_table

NC_Dispatch* UDF1_dispatch_table = NULL

Definition at line 48 of file dfile.c.

UDF1_magic_number

char UDF1_magic_number[NC_MAX_MAGIC_NUMBER_LEN+1] = ""

Definition at line 49 of file dfile.c.