evsend.cpp

#include <dirent.h>
#include <fcntl.h>
#include <linux/input.h>
#include <sys/types.h>
#include <unistd.h>

#include <cerrno>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <iostream>

/** Simple program to send events to /dev/input/eventX devices, useful
    for toggling LEDs and such */
int main(int argc, char** argv) {
  if (argc != 5) {
    std::cout << "Usage: " << argv[0] << " DEVICE TYPE CODE VALUE" << std::endl;
  } else {
    const char* filename = argv[1];
    struct input_event event;
    event.type = atoi(argv[2]);
    event.code = atoi(argv[3]);
    event.value = atoi(argv[4]);

    int fd = open(filename, O_RDWR);
    if (fd < 0) {
      std::cout << argv[0] << ": couldn't access: " << filename << ": "
                << strerror(errno) << std::endl;
    } else {
      if (write(fd, &event, sizeof(event)) != sizeof(event)) {
        std::cout << argv[0] << ": write error: " << filename << ": "
                  << strerror(errno) << std::endl;
      } else {
        // std::cout << "Send: Event(type: " << event.type << ", code: " <<
        // event.code << ", value: " << event.value << ")" << std::endl;
      }
      close(fd);
    }
  }

  return 0;
}

/* EOF */