ngcppShMem.c File Reference

#include <ngc/core/ngcpp.h>

Classes
struct	SHDATA_T

Functions
int	ngcppShDataAttach (int shared, int n, size_t size, char *erms)
int	ngcppShDataClose (void)
int	ngcppShDataGetPtr (char **ptr, int id, int len, char *erms)
char *	ngcppShDataSetPtr (int id, int *len, char *erms)
void	ngcppShDataSwap (int id)
int	ngcppShDataValid (int id)
int	ngcppShDataInvalid (int id)
int	ngcppShDataIsValid (int id)

Variables
int	ngcppKeyVal = (key_t) 0x01000000

Detailed Description

Copyright

SPDX-FileCopyrightText: 2026 European Southern Observatory (ESO) SPDX-License-Identifier: LGPL-3.0-only

Function Documentation

ngcppShDataAttach()

int ngcppShDataAttach	(	int	shared,
		int	n,
		size_t	size,
		char *	erms )

Attach to a memory data structure. If the shared flag is set the memory area is placed in shared memory.

ngcppShDataClose()

int ngcppShDataClose

(

void

)

Remove the attached shared memory data structure.

ngcppShDataGetPtr()

int ngcppShDataGetPtr	(	char **	ptr,
		int	id,
		int	len,
		char *	erms )

Return a pointer to the mirror of a shared memory data entry identified by id. The parameter len returns the maximum length of the dataset.

ngcppShDataInvalid()

int ngcppShDataInvalid

(

int

id

)

Mark an entry as not containing valid data.

ngcppShDataIsValid()

int ngcppShDataIsValid

(

int

id

)

Return 1 in case the data set contains valid data.

ngcppShDataSetPtr()

char * ngcppShDataSetPtr	(	int	id,
		int *	len,
		char *	erms )

Return in a pointer to the mirror of a shared memory data entry identified by id. The parameter len returns the maximum length of the dataset.

ngcppShDataSwap()

void ngcppShDataSwap

(

int

id

)

Swap all datasets matching id (id can be or'ed).

ngcppShDataValid()

int ngcppShDataValid

(

int

id

)

Mark an entry as containing valid data.

Variable Documentation

ngcppKeyVal

int ngcppKeyVal = (key_t) 0x01000000

Shared memory key