I’m new to pthread and mutex lock. I used them before but in a single file (main.c that creates the threads and locks are in the same file as functions and memory that use the locks). How to define mutex lock in C files that depend on each other? Ideally, I wish not to change the current structure.
我是pthread和互斥锁的新手。我之前使用过它们但是在一个文件中（main.c创建线程和锁在与使用锁的函数和内存相同的文件中）。如何在彼此依赖的C文件中定义互斥锁？理想情况下，我希望不要改变目前的结构。
main.c // create threads, include `file1.h`
file1.h
file1.c // include `file1.h` and `lib.h`, extern a memory defined in `lib.c`
lib.h
lib.c // include `lib.h`, contain functions that malloc and dealloc memory, which need to be accessed by many threads
1 个解决方案
#1
2
You need to define the mutex in one of the .c files:
您需要在其中一个.c文件中定义互斥锁：
pthread_mutex_t mux;
and then you need to forward-declare it in one of the .h files:
然后你需要在其中一个.h文件中转发声明它：
extern pthread_mutex_t mux;
The normal convention is that you put the forward declaration in the .h file corresponding to the .c file, but there's no reason you couldn't put it in a different .h file; you just have to remember which .h to include. Make sure you include the .h file where the variable is defined and everywhere that it is used.
通常的惯例是你将.e文件中的前向声明放在.c文件中，但没有理由你不能把它放在一个不同的.h文件中;你只需要记住要包括哪个.h。确保包含定义变量的.h文件以及使用它的所有位置。
#1
2
You need to define the mutex in one of the .c files:
您需要在其中一个.c文件中定义互斥锁：
pthread_mutex_t mux;
and then you need to forward-declare it in one of the .h files:
然后你需要在其中一个.h文件中转发声明它：
extern pthread_mutex_t mux;
The normal convention is that you put the forward declaration in the .h file corresponding to the .c file, but there's no reason you couldn't put it in a different .h file; you just have to remember which .h to include. Make sure you include the .h file where the variable is defined and everywhere that it is used.
通常的惯例是你将.e文件中的前向声明放在.c文件中，但没有理由你不能把它放在一个不同的.h文件中;你只需要记住要包括哪个.h。确保包含定义变量的.h文件以及使用它的所有位置。