we developed a set of system V semphore interface for our application, in general, all of them work normal, seldom cause the deadlock. Here are some important sem_wait and sem_post interface, pls point some suggestion to fixed the deadlock problem:
how can I lock my keyboard while I'm away from the computer without using lock command. What other commands gives me the option to lock keyboard device?
thanks (7 Replies)
Hello,there
here is my code about semphore, when calling it in the program,sometimes result in the deadlock of semphore, but I can not find it, anyone can point some bugs and give some suggestion?
#define BIGCOUNT 888 // initial value of process counter
#define SEM_POST_LIMIT 3 ... (0 Replies)
Hi all,
I have a directory where some process is keeping incremental/new log files. I need to code a program which will periodically poll this directory and if it founds a new file arrived then copy that new file to some other specific directory.
We are OK with this polling approach. I just... (3 Replies)
Hi,
I have some problem with following command.
$path='pwd'.”/pack”;
When I check the value in the variable path , it give the following output
/tmp/new /pack
The pwd will be /tmp/new
Now the problem is the spaces is added between pwd and the appended path.
I need the output like... (5 Replies)
Hello,
this is solaris 10 on SF v440,
I know below errors might go away if I put a new PS or put the original one back in socket but is there any other way to stop these errors from appearing in /var/adm/messages ? I do not want to put the failed PS1 in socket neither do we want to spend on... (5 Replies)
Hello all,
If anyone has time, I have a few questions:
How do I do the following in Linux. We are using Red Hat and Oracle Enterprise Linux, which is based on Red Hat too.
1. How to lock the account after a few (like 3) invalid password attempts?
2. How do you lock a screen after 30... (1 Reply)
Hi,
I am having multiple echo statements to print output
echo "$VAr"
echo "$lenght"
echo "$sum"
I get the output as
12
24
36
I need the output to be 12 24 36.
How do i arrive at this.
Thanks in advance (4 Replies)
Hi all,
I have to test some user priviliges. The goal is to be sure that an unauthorized user can't restart some modules (ssh, mysql etc...).
I'm trying to automate it with a shell script but in same cases I got the syslog broadcast message.
Is there any way to simply get a return code... (3 Replies)
Hi I have a script which runs the isql command and takes the output in a xls file.
Is there a way to trim the spaces(leading and trailing) from all the values in the column of the xls sheet? (6 Replies)
Discussion started by: Sharma331
6 Replies
LEARN ABOUT LINUX
sem_post
SEM_POST(3) Linux Programmer's Manual SEM_POST(3)NAME
sem_post - unlock a semaphore
SYNOPSIS
#include <semaphore.h>
int sem_post(sem_t *sem);
Link with -lrt or -pthread.
DESCRIPTION
sem_post() increments (unlocks) the semaphore pointed to by sem. If the semaphore's value consequently becomes greater than zero, then
another process or thread blocked in a sem_wait(3) call will be woken up and proceed to lock the semaphore.
RETURN VALUE
sem_post() returns 0 on success; on error, the value of the semaphore is left unchanged, -1 is returned, and errno is set to indicate the
error.
ERRORS
EINVAL sem is not a valid semaphore.
EOVERFLOW
The maximum allowable value for a semaphore would be exceeded.
CONFORMING TO
POSIX.1-2001.
NOTES
sem_post() is async-signal-safe: it may be safely called within a signal handler.
EXAMPLE
See sem_wait(3).
SEE ALSO sem_getvalue(3), sem_wait(3), sem_overview(7)COLOPHON
This page is part of release 3.27 of the Linux man-pages project. A description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
Linux 2009-03-30 SEM_POST(3)