08-24-2007
Hi blowtorch,
Thanks a lot..
I agree with you... when it is only message queue and message queue details we can manage with file...
here in this scenario as i have given the structures of mutex and condition variables too.... and i donno exactly what details of pthread_mutex_t should be stored in file while we are locking and unlocking the mutex, the same applies for condition variable...
could you pls.. clarify this to me..
FYI
typedef union
{
struct
{
int __lock;
unsigned int __count;
int __owner;
/* KIND must stay at this position in the structure to maintain
binary compatibility. */
int __kind;
unsigned int __nusers;
int __spins;
} __data;
char __size[__SIZEOF_PTHREAD_MUTEX_T];
long int __align;
} pthread_mutex_t;
thanks,
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LEARN ABOUT SUNOS
mqueue.h
mqueue.h(3HEAD) Headers mqueue.h(3HEAD)
NAME
mqueue.h, mqueue - message queues
SYNOPSIS
#include <mqueue.h>
DESCRIPTION
The <mqueue.h> header defines the mqd_t type, which is used for message queue descriptors. This will not be an array type. A message
queue descriptor may be implemented using a file descriptor, in which case applications can open up to at least OPEN_MAX file and message
queues.
The <mqueue.h> header defines the sigevent structure (as described in <signal.h>, see signal.h(3HEAD)) and the mq_attr structure, which is
used in getting and setting the attributes of a message queue. Attributes are initially set when the message queue is created. A mq_attr
structure has the following members:
long mq_flags message queue flags
long mq_maxmsg maximum number of messages
long mq_msgsize maximum message size
long mq_curmsgs number of messages currently queued
Inclusion of the <mqueue.h> header may make visible symbols defined in the headers <fcntl.h>, <signal.h>, <sys/types.h>, and <time.h>.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Interface Stability |Standard |
+-----------------------------+-----------------------------+
SEE ALSO
fcntl.h(3HEAD), signal.h(3HEAD), time.h(3HEAD), types.h(3HEAD), attributes(5), standards(5)
SunOS 5.10 30 Aug 2002 mqueue.h(3HEAD)