我有一些问题让 双方 使用的代码边uinput工作。
uinput
基于uinput入门:用户级别输入子系统[死链接;存档 ]我总结了以下 作家 (减去错误处理):
int main(int ac, char **av) { int fd = open("/dev/uinput", O_WRONLY | O_NONBLOCK); int ret = ioctl(fd, UI_SET_EVBIT, EV_ABS); ret = ioctl(fd, UI_SET_ABSBIT, ABS_X); struct uinput_user_dev uidev = {0}; snprintf(uidev.name, UINPUT_MAX_NAME_SIZE, "uinput-rotary"); uidev.absmin[ABS_X] = 0; uidev.absmax[ABS_X] = 255; ret = write(fd, &uidev, sizeof(uidev)); ret = ioctl(fd, UI_DEV_CREATE); struct input_event ev = {0}; ev.type = EV_ABS; ev.code = ABS_X; ev.value = 42; ret = write(fd, &ev, sizeof(ev)); getchar(); ret = ioctl(fd, UI_DEV_DESTROY); return EXIT_SUCCESS; }
这似乎可行,至少input_event似乎已编写了完整的结构。
input_event
然后,我写出了我最能想到的事件的天真的 读者 :
int main(int ac, char **av) { int fd = open(av[1], O_RDONLY); char name[256] = "unknown"; ioctl(fd, EVIOCGNAME(sizeof(name)), name); printf("reading from %s\n", name); struct input_event ev = {0}; int ret = read(fd, &ev, sizeof(ev)); printf("Read an event! %i\n", ret); printf("ev.time.tv_sec: %li\n", ev.time.tv_sec); printf("ev.time.tv_usec: %li\n", ev.time.tv_usec); printf("ev.type: %hi\n", ev.type); printf("ev.code: %hi\n", ev.code); printf("ev.value: %li\n", ev.value); return EXIT_SUCCESS; }
不幸的是,读者方面根本无法工作。每次只能读取8个字节,这几乎不是完整的input_event结构。
我犯了什么愚蠢的错误?
您还应该在实际事件之后编写一个同步事件。在您的编写方代码中:
struct input_event ev = {0}; ev.type = EV_ABS; ev.code = ABS_X; ev.value = 42; usleep(1500); memset(&ev, 0, sizeof(ev)); ev.type = EV_SYN; ev.code = 0; ev.value = 0; ret = write(fd, &ev, sizeof(ev)); getchar();