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Top Forums Programming Need help with fork, forking multiple childs and shared memory Post 302339393 by helpmeforlinux on Thursday 30th of July 2009 11:17:20 AM
Old 07-30-2009
Computer

#matrixmadhan

No the no of first level children as well as second node level children are not constant all are dynamic.

What i m doing is as below
- I m looking for total networks.
- then i fork that many child's for network level this is my first level
- now on each first level child i m counting no of nodes
- and here i m forking second level children.
- now the second level child will be there till the network is there.

means the first level child will be running till the network is there, and the second level child will be running still there are nodes.
so both the first level and second level chidren are there for some much amount of time.

now in second level children i m doing some x type of task and calling
kill signal as kill(getppid(), userdefined signal) to the parent.

now the problem is i m not able to identify which children gave the interrupt to parent , i have signal handler but in that signal handler how do i identify which child have sent me the signal.

If i identify the child then i can again assign that child some pending task for waiting node in node list.

If you want can post my whole code. i m really stuck over here.

Any suggestions.
 

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pthread_atfork(3T)														pthread_atfork(3T)

NAME
pthread_atfork() - register fork handlers. SYNOPSIS
PARAMETERS
prepare This function is called before performing the parent This function is called in the parent process after performing the child This function is called in the child process after performing the DESCRIPTION
The function allows an application to install fork handlers. These fork handlers will be called before and after a operation. These han- dlers will be called in the context of the thread calling Similar to the handlers, the application does not need to do anything special for these fork handlers to be called. They will be invoked by the system when a operation occurs. The function is called before the operation in the parent process. The function is called after the operation in the parent process. The function is called after the operation in the child process. If a fork handler is not needed in one or more of these three places, the appropriate fork handler parameter may be set to NULL. A process may install multiple fork handling functions. The and fork handlers will be called in the order in which they were installed (i.e., The fork handlers will be called in the opposite order (i.e., RETURN VALUE
Upon successful completion, returns zero. Otherwise, an error number is returned to indicate the error (the variable is not set). ERRORS
If any of the following occur, the function returns the corresponding error number: [ENOMEM] There is insufficient table space to install the fork handlers. AUTHOR
was derived from the IEEE POSIX P1003.1c standard. SEE ALSO
fork(2), atexit(3). STANDARDS CONFORMANCE
Pthread Library pthread_atfork(3T)
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