From 359bcaa539d9bbb2b008b5fd0a76c758b489bed5 Mon Sep 17 00:00:00 2001 From: Guido van Rossum Date: Fri, 14 Nov 1997 22:24:28 +0000 Subject: This fix (across 4 files in 3 directories) solves a subtle problem with signal handlers in a fork()ed child process when Python is compiled with thread support. The bug was reported by Scott . What happens is that after a fork(), the variables used by the signal module to determine whether this is the main thread or not are bogus, and it decides that no thread is the main thread, so no signals will be delivered. The solution is the addition of PyOS_AfterFork(), which fixes the signal module's variables. A dummy version of the function is present in the intrcheck.c source file which is linked when the signal module is not used. --- Include/intrcheck.h | 1 + Modules/posixmodule.c | 1 + Modules/signalmodule.c | 9 +++++++++ Parser/intrcheck.c | 5 +++++ 4 files changed, 16 insertions(+) diff --git a/Include/intrcheck.h b/Include/intrcheck.h index f9658e2..8566051 100644 --- a/Include/intrcheck.h +++ b/Include/intrcheck.h @@ -37,6 +37,7 @@ PERFORMANCE OF THIS SOFTWARE. extern int PyOS_InterruptOccurred Py_PROTO((void)); extern void PyOS_InitInterrupts Py_PROTO((void)); +void PyOS_AfterFork Py_PROTO((void)); #ifdef __cplusplus } diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c index e06827a..58111ef 100644 --- a/Modules/posixmodule.c +++ b/Modules/posixmodule.c @@ -1082,6 +1082,7 @@ posix_fork(self, args) pid = fork(); if (pid == -1) return posix_error(); + PyOS_AfterFork(); return PyInt_FromLong((long)pid); } #endif diff --git a/Modules/signalmodule.c b/Modules/signalmodule.c index e815492..e91c3cb 100644 --- a/Modules/signalmodule.c +++ b/Modules/signalmodule.c @@ -613,3 +613,12 @@ PyOS_InterruptOccurred() } return 0; } + +void +PyOS_AfterFork() +{ +#ifdef WITH_THREAD + main_thread = get_thread_ident(); + main_pid = getpid(); +#endif +} diff --git a/Parser/intrcheck.c b/Parser/intrcheck.c index a2a3145..7fe6205 100644 --- a/Parser/intrcheck.c +++ b/Parser/intrcheck.c @@ -219,3 +219,8 @@ PyOS_InterruptOccurred() } #endif /* !OK */ + +void +PyOS_AfterFork() +{ +} -- cgit v0.12