Visit Our UNIX and Linux User Community

SHMMAX (semaphores)

Thread Tools Search this Thread
Top Forums UNIX for Dummies Questions & Answers SHMMAX (semaphores)
# 1  
Old 01-05-2008
SHMMAX (semaphores)

How can I change the semaphore values? Without say writing a C program that calls the method.

# 2  
Old 01-05-2008
Originally Posted by JamesByars
How can I change the semaphore values? Without say writing a C program that calls the method.

depends on the os you are using...
# 3  
Old 01-06-2008
Originally Posted by DukeNuke2
depends on the os you are using...
I am using HP-UX
# 4  
Old 01-06-2008
and i only know it for solaris Smilie
# 5  
Old 01-06-2008
There are a number of possibilities:



Also see the kmtune command and man page.
# 6  
Old 01-06-2008
Thanks guys

Previous Thread | Next Thread
Test Your Knowledge in Computers #503
Difficulty: Easy
The flow of control (or simply control flow) is how a program processes its instructions.
True or False?

10 More Discussions You Might Find Interesting

1. Solaris


Hi, Can somebody please explain me what semaphores are? there purpose? and there effects? Thanks in advance:) (0 Replies)
Discussion started by: Laxxi
0 Replies

2. Programming

about Semaphores

Hello Everybody, I am building a server. this server contains some data. Clients may modify this data or read this data. If a client is reading the data and at the same time another client is modifying the data then at this case the reading client may read some false data (some old mixed with... (1 Reply)
Discussion started by: Omar_Mokhtar
1 Replies

3. UNIX for Dummies Questions & Answers


I am having problem with semaphores. I am trying to protect line where process prints so that every process with print in proper order.This is the code.. #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <sys/ipc.h> #include <sys/sem.h> #include <sys/types.h> union... (3 Replies)
Discussion started by: joker40
3 Replies

4. SuSE

extremly huge shmmax value

Hello all! On this SLES 10 box I found (what I think) an abnormal huge shmmax value. hostname:~ # cat /proc/sys/kernel/shmmax 18446744073709551615 hostname:~ # Perhaps there is a malconfigured startup script on the machine somwhere? But where/how do I find/set the default value of... (2 Replies)
Discussion started by: sap4ever
2 Replies

5. UNIX for Advanced & Expert Users

Help on SHMMAX

Hi. Allocated is showing in hexadecimal which comes to 1 GB But the usage is showing more (14 GB). Can you please explain why? Normally, usage should be less than allocated $ /usr/sbin/kmtune -q shmmax Parameter Current... (4 Replies)
Discussion started by: somesh_p
4 Replies

6. UNIX for Advanced & Expert Users

How many semaphores?

Hello, first of all I apologize if this thread is not in the correct section of this forum, but this one just seemed the most appropriate. The question I have does not concern Unix specifically, it applies to virtually any OS, however it is in Unix where I learned about this problem. So, the... (8 Replies)
Discussion started by: Watto86
8 Replies

7. Programming

semaphores using up and down

been searching around on how to use an up and down function with semaphores but i can't find an example. i looked into using: "semop" but i have no idea how to use it. I have been able to declared the semaphores using semget and initializing them using semctl. (7 Replies)
Discussion started by: ddx08
7 Replies

8. Shell Programming and Scripting


Hi Friends, If i execute this command it comes back with 300 lines: ipcs|grep cerebrus >>> i would like to clear the semaphores but ipcrm can remove one id at a time. is there a quicker way of removing semaphores maybe using awk? Regards, (1 Reply)
Discussion started by: kekanap
1 Replies

9. Programming


Hi there, Could someone please confirm which POSIX semaphore routines should be used for a multiprocess (and not multithreaded) environment? sys/sem.h definitely works. but the routines, semget, semctl, semop are pretty unwieldy. So, I am looking for an easier way out. From the man pages... (2 Replies)
Discussion started by: qntmteleporter
2 Replies

10. Programming


Dear Reader, I'm in a multiprocess environment working with shared mem and semaphores as mutex.. The problem is -- If one of the process hooked up with the semaphore and accessing the shared mem, terminates abruptly ( or got killed ), other process which are in want of the semaphore are... (1 Reply)
Discussion started by: joseph_shibu
1 Replies

Featured Tech Videos