将 C++ 程序连接到具有共享内存的 Python 脚本

冒昧地在这里发布一个POSIX共享内存段的工作示例，它将在类似Linux/Unix的系统上跨C/C++和Python工作.这个可以在Windows上运行not.

用于创建数据并将数据写入共享内存段的C++代码(命令行上提供的名称):

#include <sys/mman.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>

#include <iostream>
#include <string>

int main(int argc, char * argv[])
{
    if (argc != 2) {
         std::cerr << "Argument <shmem_name> required" << std::endl;
         return 1;
    }
    const char * shmem_name = argv[1];
    size_t shm_size = 4096;
    int shmem_fd = shm_open(shmem_name, O_CREAT|O_RDWR, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP);
    if (shmem_fd == -1) {
         perror("shm_open");
         return 1;
    }
    std::cout << "Shared Memory segment created with fd " << shmem_fd << std::endl;
    if (ftruncate(shmem_fd, shm_size) == -1) {
        perror("ftruncate");
        return 1;
    }
    std::cout << "Shared Memory segment resized to " << shm_size << std::endl;
    void * addr = mmap(0, shm_size, PROT_WRITE, MAP_SHARED, shmem_fd, 0);
    if (addr == MAP_FAILED) {
        perror("mmap");
        return 1;
    }
    std::cout << "Please enter some text to write to shared memory segment\n";
    std::string text;
    std::getline(std::cin, text);
    while (! text.empty()) {
        strncpy((char *)addr, text.data(), shm_size);
        std::cout << "Written '" << text << "' to shared memory segment\n";
        std::getline(std::cin, text);
    }
    std::cout << "Unlinking shared memory segment." << std::endl;
    shm_unlink(shmem_name) ;
}

从共享内存段的开头读取任何字符串的Python代码:

import sys
from multiprocessing import shared_memory, resource_tracker

if len(sys.argv) != 2:
    print("Argument <shmem_name> required")
    sys.exit(1)

shm_seg = shared_memory.SharedMemory(name=sys.argv[1])
print(bytes(shm_seg.buf).strip(b'\x00').decode('ascii'))
shm_seg.close()
# Manually remove segment from resource_tracker, otherwise shmem segment
# will be unlinked upon program exit
resource_tracker.unregister(shm_seg._name, "shared_memory")