02-26-2002
Nothing that you're saying makes any sense at all.
A process has total control over when a child is created. When it invokes fork(), that is exactly when the process is created. The child exists when the very next statement is executed.
There is no need at all to synchonize the reading and writing on a pipe. The reader do can invoke read() hours before the data is written...it will simply wait unless it sets O_NDELAY in which case it returns immediately...so don't set that option. The reader can also read() hours after the write() on the other end. The data will wait. Neither case can cause a broken pipe, which is the error you complained about. That is caused by the reader exiting prior to the write.
Your real problem is that you'e trying to run a marathon when you can't yet walk.
If you attempt to use pipes in a full-duplex manner or use two pipe to achieve a two-way communication between processes, you will almost certainly cause deadlock. Get the data flowing in a single direction before you try to move on.
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