10 More Discussions You Might Find Interesting
1. Programming
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
2. AIX
1.How to know wich process is using the shared memory?
2.How to flush (release) the process from the shared memory? (1 Reply)
Discussion started by: pchangba
1 Replies
3. UNIX for Advanced & Expert Users
Hi,
Using ipcs we can see shared memory, etc.. details. How can I add/remove shared memory(command name)?
Thanks,
Naga:cool: (2 Replies)
Discussion started by: Nagapandi
2 Replies
4. Programming
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)
Discussion started by: otheus
0 Replies
5. Programming
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)
Discussion started by: DreamWarrior
12 Replies
6. Programming
hi,
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?
//example
typedef struct node
{
int x;
char c;
struct node *next;
} node;
or i should send the items ( x,c ) by... (9 Replies)
Discussion started by: elzalem
9 Replies
7. Programming
what i want to do is have an int that can been written into by 2 processes but my code doesn't seem to work.
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/sem.h>
#include <sys/shm.h>
#include<stdio.h>
#define KEY1 (1492)
int main()
{
int shmid;
volatile int * addr;... (6 Replies)
Discussion started by: ddx08
6 Replies
8. Programming
hi all
I have been asked to implement shared memory in user mode?But :rolleyes: im not understanding how to do this.And what does it mean in user mode?Is it that we need to simulate what kernal does...like attaching ,detaching memory..etc...?
And would also like to know why shared memory is... (3 Replies)
Discussion started by: vijaya2006
3 Replies
9. UNIX for Advanced & Expert Users
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)
Discussion started by: cjcamaro
1 Replies
10. Programming
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)
Discussion started by: joseph_shibu
1 Replies
IPCMK(1) User Commands IPCMK(1)
NAME
ipcmk - make various IPC resources
SYNOPSIS
ipcmk [options]
DESCRIPTION
ipcmk allows you to create shared memory segments, message queues, and semaphore arrays.
OPTIONS
Resources can be specified with these options:
-M, --shmem size
Create a shared memory segment of size bytes. The size argument may be followed by the multiplicative suffixes KiB (=1024), MiB
(=1024*1024), and so on for GiB, etc. (the "iB" is optional, e.g., "K" has the same meaning as "KiB") or the suffixes KB (=1000), MB
(=1000*1000), and so on for GB, etc.
-Q, --queue
Create a message queue.
-S, --semaphore number
Create a semaphore array with number of elements.
Other options are:
-p, --mode mode
Access permissions for the resource. Default is 0644.
-V, --version
Display version information and exit.
-h, --help
Display help text and exit.
SEE ALSO
ipcrm(1), ipcs(1)
AUTHOR
Hayden A. James <hayden.james@gmail.com>
AVAILABILITY
The ipcmk command is part of the util-linux package and is available from Linux Kernel Archive <https://www.kernel.org/pub/linux/utils
/util-linux/>.
util-linux July 2014 IPCMK(1)