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Full Discussion: forks, ipc, fifos, update issues...
Top Forums Programming forks, ipc, fifos, update issues... Post 84949 by Funktar on Thursday 29th of September 2005 02:59:40 PM
Old 09-29-2005
so program starts, main forks and executes child1, there's some communication, child1 sends a spawn message to main, but the new child needs to wait until the first child finishes. So, main forks, new child adds itself to the task table and begins to wait until child1 is finished. Main proceeds with child1 until it's done. Immediately after child1 is done, the new child executes child2, etc. I need to tell my main that there is a child waiting, and the order of execution so I use a task table. problem is after child1 is done, while new child (not yet executed child2) is waiting, main checks tasktable to see if there's another entry, which for some reason there isn't, but there should be.

and no, show is a call to TaskTable class which just displays entries. Any more questions just ask. Thanks for help.
 

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LEARN ABOUT OPENSOLARIS

ipc.h

ipc.h(3HEAD)							      Headers							      ipc.h(3HEAD)

NAME

       ipc.h, ipc - XSI interprocess communication access structure

SYNOPSIS

       #include <sys/ipc.h>

DESCRIPTION

       The <sys/ipc.h> header is used by three mechanisms for interprocess communication (IPC): messages, semaphores, and shared memory. All use a
       common structure type, ipc_perm, to pass information used in determining permission to perform an IPC operation.

       The ipc_perm structure contains the following members:

	 uid_t	uid	/* owner's user ID */
	 gid_t	gid	/* owner's group ID */
	 uid_t	cuid	/* creator's user ID */
	 gid_t	cgid	/* creator's group ID */
	 mode_t mode	/* read/write permission

       The uid_t, gid_t, mode_t, and key_t types are defined as described in <sys/types.h>. See types.h(3HEAD).

       Definitions are provided for the constants listed below.

       Mode bits:

       IPC_CREAT     Create entry if key does not exist.

       IPC_EXCL      Fail if key exists.

       IPC_NOWAIT    Error if request must wait.

       Keys:

       IPC_PRIVATE    Private key.

       Control commands:

       IPC_RMID    Remove identifier.

       IPC_SET	   Set options.

       IPC_STAT    Get options.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Standard			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       ftok(3C), types.h(3HEAD), attributes(5), standards(5)

SunOS 5.11							    10 Sep 2004 						      ipc.h(3HEAD)
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