I reported this problem a few months ago in bug-glibc and did not get any response, although that is not unexpected since it is unclear where the problem is. So that bug report and this report will probably serve just to chronicle the problem in case anybody sees something similar. Anyhow, the problem is that somehow fork or vfork (makes no difference) will return an apparently valid pid and then the child process will disappear. Calling wait or waitpid will return errno 10 (ECHILD, "no child process"), and will continue to return errno 10 if wait or waitpid is called again. I got lucky with some strategically placed printf's at a point where this problem sometimes appears and was able to determine that, at least when wait() is called, the signal handler for SIGCLD (17) is SIG_IGN (1), so it seems less likely that some userland facility is reaping the process, especially since one of the places where this problem occurs is a very simple program that does little more than fork and wait. This usually happens during the "configure" phase of our build process, which is right after about 2.5GB of sources have been extracted from CVS to a directory tree, so there may be some IO congestion that could lead to unusual timing relationships, leading to unsual results from race conditions. Also, the problem started occurring occasionally when the machine in question got an 866MHz CPU, and started occuring more often when it got a 1GHz CPU. So, more instructions per time slice seems to be a relevant factor. Anyhow, I know this is a very slippery bug and it may be months before it is tracked down either here or elsewhere, but I thought it would be helpful to at least document it for the linux-kernel archives. Adam J. Richter __ ______________ 4880 Stevens Creek Blvd, Suite 104 [EMAIL PROTECTED] \ / San Jose, California 95129-1034 +1 408 261-6630 | g g d r a s i l United States of America fax +1 408 261-6631 "Free Software For The Rest Of Us." - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] Please read the FAQ at http://www.tux.org/lkml/