act_fils.sa_handler= fonction_fils; // no function call () parentheses
我们需要函数本身，而不是函数调用的返回值。
其次，该函数必须具有适合信号处理程序的类型：
void fonction_fils(int sig)
{
}
请注意，在 C 语言中，与 C++ 不同，如果将函数参数列表声明为 ()，则该函数将声明为具有未知的参数类型信息。函数定义是一个不带参数的函数，与(void)兼容，但作为声明，它不会向周围的程序说明这一点。
Firstly, when a signal handler is registered, the function isn't supposed to be called at that time. Rather, a pointer to the function is required: the pointer is stored into the sigaction structure:
act_fils.sa_handler= fonction_fils; // no function call () parentheses
We want the funtion itself, not the return value from a call to the function.
Secondly, the function has to have the right type for a signal handler:
void fonction_fils(int sig)
{
}
Note that in the C language, unlike C++, if you declare a function paramter list as (), it declares the function as having an unknown parameter type information. The function definition is one that takes no arguments, compatible with (void), but as a declaration it doesn't say that to the surrounding program.
sa_handler specifies the action to be associated with signum and
is be one of the following:
* SIG_DFL for the default action.
* SIG_IGN to ignore this signal.
* A pointer to a signal handling function. This function
receives the signal number as its only argument.
Instead of statements like these
act_fils.sa_handler= fonction_fils();
and
act_pere.sa_handler=fonction_pere();
where there are used function calls that have the return type void you need to write
act_fils.sa_handler= fonction_fils;
and
act_pere.sa_handler=fonction_pere;
to assign function pointers.
Pay attention to that for example the data member sa_handler has the type
void (*sa_handler)(int);
So the corresponding function shall have the same type.
From the documentation
sa_handler specifies the action to be associated with signum and
is be one of the following:
* SIG_DFL for the default action.
* SIG_IGN to ignore this signal.
* A pointer to a signal handling function. This function
receives the signal number as its only argument.
发布评论
评论（2）
首先，当注册信号处理程序时，此时不应调用该函数。相反，需要一个指向函数的指针：该指针存储在 sigaction 结构中：
我们需要函数本身，而不是函数调用的返回值。
其次，该函数必须具有适合信号处理程序的类型：
请注意，在 C 语言中，与 C++ 不同，如果将函数参数列表声明为
()，则该函数将声明为具有未知的参数类型信息。函数定义是一个不带参数的函数，与(void)兼容，但作为声明，它不会向周围的程序说明这一点。Firstly, when a signal handler is registered, the function isn't supposed to be called at that time. Rather, a pointer to the function is required: the pointer is stored into the
sigactionstructure:We want the funtion itself, not the return value from a call to the function.
Secondly, the function has to have the right type for a signal handler:
Note that in the C language, unlike C++, if you declare a function paramter list as
(), it declares the function as having an unknown parameter type information. The function definition is one that takes no arguments, compatible with(void), but as a declaration it doesn't say that to the surrounding program.而不是像这样的语句
以及
使用具有返回类型 void 的函数调用
您需要编写并
分配函数指针，
。注意，例如数据成员sa_handler具有类型，
因此相应的函数应具有相同的类型。
从文档中
Instead of statements like these
and
where there are used function calls that have the return type void you need to write
and
to assign function pointers.
Pay attention to that for example the data member
sa_handlerhas the typeSo the corresponding function shall have the same type.
From the documentation