Manpages - drmHandleEvent.3

drmHandleEvent - read and process pending DRM events

#include <xf86drm.h>

int drmHandleEvent(int fd, drmEventContextPtr evctx);

drmHandleEvent processes outstanding DRM events on the DRM file-descriptor passed as fd. This function should be called after the DRM file-descriptor has polled readable; it will read the events and use the passed-in evctx structure to call function pointers with the parameters noted below:

#+begin_quote

      typedef struct _drmEventContext {
          int version;
          void (*vblank_handler) (int fd,
                                  unsigned int sequence,
                                  unsigned int tv_sec,
                                  unsigned int tv_usec,
                                  void *user_data)
          void (*page_flip_handler) (int fd,
                                     unsigned int sequence,
                                     unsigned int tv_sec,
                                     unsigned int tv_usec,
                                     void *user_data)
      } drmEventContext, *drmEventContextPtr;

#+end_quote

drmHandleEvent returns 0 on success, or if there is no data to read from the file-descriptor. Returns -1 if the read on the file-descriptor fails or returns less than a full event record.

Bugs in this function should be reported to https://gitlab.freedesktop.org/mesa/drm-issues

*drm*(7), *drm-kms*(7), *drmModePageFlip*(3), *drmWaitVBlank*(3)