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Re: crash if fork(2) from another thread
On Sun, Sep 28, 2008 at 09:32:39AM +0200, V??clav Haisman wrote:
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>Hirokazu Yamamoto wrote, On 28.9.2008 4:16:
>> # I've post mail, but it didn't show up in
>> http://www.nabble.com/Cygwin-f12165.html.
>> # Maybe it was not good to attach a file. So try again...
>>
>> I'm not familiar with pthread & fork, but I think following code should not
>> crash. Is this expected behavior?
>>
>> #include <stdio.h>
>> #include <stdlib.h>
>> #include <pthread.h>
>> #include <assert.h>
>>
>> void *thread_func(void* args)
>> {
>> int ret;
>> pid_t pid;
>> pthread_t thread;
>>
>> puts("thread_func");
>>
>> pid = fork();
>>
>> assert(pid != (pid_t)-1);
>>
>> if (pid != 0) /* parent process */
>> {
>> int status;
>>
>> printf("parent process (child pid = %d)\n", pid);
>>
>> waitpid(pid, &status, 0);
>>
>> puts("parent process end");
>> }
>> else /* child process */
>> {
>> puts("child process"); /* crash here */
>I think this is not allowed in here. You can only do async-signal-safe
>stuff in the child. IO is AFAIK not in that category. Basically, the
>only thing you can safely do in the child process is to call exec().
I don't see any reason why this shouldn't be allowed. You should
be able to do anything you want in a child process.
cgf
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