this is the problem: i want to swap a linked list between 4 processes (unrelated), is there any way i can do that just by sending a pointer to a structure?
or i should send the items ( x,c ) by value and reconstruct the list ?
my solution: create the list in a shared location in memory, where all the processes can use the same reference to manipulate or read the list, but if i use malloc(); i can't control the physical place where the memory is allocated (that's what i know)
Dear Reader,
Is is necessary to attach / dettach the shared memory segments for write operations , if more than one program is accessing same shared memory segments..
I have used semaphore mutex and still I'm getting segmentation fault when I write to the segment when other program is already... (1 Reply)
I am running HP-UX B.11.11.
I'm increasing a parameter for a database engine so that it uses more memory to buffer the disk drive (to speed up performance). I have over 5GB of memory not being used.
But when I try to start the DB with the increased buffer parameter I get told.
"Not... (1 Reply)
Hi all :confused: ,
I am new to unix.I have been asked to implement shared memory in user's mode.What does this mean?What is the difference it makes in kernel mode and in users mode?What are the advantages of this impemenation(user's mode)?
And also i would like to know why exactly shared... (0 Replies)
I need to create a shared library to access an in memory DB. The DB is not huge, but big enough to make it cumbersome to carry around in every single process using the shared library. Luckily, it is pretty static information, so I don't need to worry much about synchronizing the data between... (12 Replies)
I am writing a shared library in Linux (but compatible with other UNIXes) and I want to allow multiple instances to share a piece of memory -- 1 byte is enough. What's the "best" way to do this? I want to optimize for speed and portability.
Obviously, I'll have to worry about mutual exclusion. (0 Replies)
Hey, Im using a shared memory segment to share a WINDOW structure among 2 processes. Basically I'm building a multi-player snake game in which multiple prrocesses access the window.
The 'parent' process initializes the shared memory segment and puts the window in it. I can access and perform... (1 Reply)
Hello.
I am new to this forum and I would like to ask for advice about low level POSIX programming.
I have to implement a POSIX compliant C shared library.
A file will have some variables and the shared library will have some functions which need those variables.
There is one special... (5 Replies)
Discussion started by: iamjag
5 Replies
LEARN ABOUT HPUX
di_devfs_path
di_devfs_path(3DEVINFO) Device Information Library Functions di_devfs_path(3DEVINFO)NAME
di_devfs_path, di_devfs_minor_path, di_devfs_path_free - generate and free physical path names
SYNOPSIS
cc [ flag... ] file... -ldevinfo [ library... ]
#include <libdevinfo.h>
char *di_devfs_path(di_node_t node);
char *di_devfs_minor_path(di_minor_t minor);
void di_devfs_path_free(char *path_buf);
PARAMETERS
node The handle to a device node in the snapshot.
minor The handle to a device minor node in the snapshot.
path_buf A pointer returned by di_devfs_path() or di_devfs_minor_path().
DESCRIPTION
The di_devfs_path() function generates the physical path of the device node specified by node.
The di_devfs_minor_path() function generates the physical path of the device minor node specified by minor.
The di_devfs_path_free() function frees memory that was allocated to store the physical path by di_devfs_path() and di_devfs_minor_path().
The caller of di_devfs_path() and di_devfs_minor_path() is responsible for freeing this memory allocated by calling di_devfs_path_free().
RETURN VALUES
Upon successful completion, the di_devfs_path() and di_devfs_minor_path() functions return a pointer to the string containing the physical
path of a device node or a device minor node, respectively. Otherwise, they return NULL and errno is set to indicate the error.
ERRORS
The di_devfs_path() and di_devfs_minor_path() functions will fail if:
EINVAL The node or minor argument is not a valid handle.
The di_devfs_path() and di_devfs_minor_path() functions can also return any error value returned by malloc(3C).
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Interface Stability |Evolving |
+-----------------------------+-----------------------------+
|MT-Level |Safe |
+-----------------------------+-----------------------------+
SEE ALSO di_init(3DEVINFO), libdevinfo(3LIB), malloc(3C), attributes(5)
Writing Device Drivers
SunOS 5.10 22 Mar 2004 di_devfs_path(3DEVINFO)
04-23-2007
memory sharing - not shared memory -
