This just appeared on comp.lang.python. Can any Zope experts comment on whether this Linux threads comment has implications for Zope? ---------- ## Forwarded Message ## ---------- Subject: Calling os.waitpid() From Secondary Thread Under Linux 2.2.12-20? Date: Tue, 11 Apr 2000 17:48:11 GMT From: rwiserREMOVEthis@mindspring.com (Randy Wiser) I've written a small python program that spawns one child process from its main thread, and then creates a second thread. The sole purpose of the second thread (at this point) is to call os.waitpid(processID, 0) to wait for the child that the main thread created. This works fine under Solaris when I call os.waitpid() from the second thread. But, under Linux 2.2.12-20 I get the following OSError exception: [Errno 10] No child processes However, if (under Linux still) I call waitpid() from the main thread (as a test), the call does indeed wait until the child process terminates. After scouring some of the Linux newsgroups, I've gathered that threads spawned under Linux may have SIGCHLD signals (and other signals) blocked, and that this _may_ be the reason I get the error, even though the processID I pass is for a valid process. Unfortunately there seems to be no easy way to set the signal mask for the second thread. Has anyone else run into this situation, and if so can you advise how you solved it? -------------------------------------------------------