Check if DRM_CLIENT_CAP_ATOMIC is supported by your GPU

Check if DRM_CLIENT_CAP_ATOMIC is supported by your GPU

make CFLAGS=$(pkg-config --cflags libdrm) LDLIBS=$(pkg-config --libs libdrm) check-drm-cap-atomic && ./check-drm-cap-atomic

check-drm-cap-atomic.c

#include <stdio.h>
#include <assert.h>
#include <errno.h>

#include <fcntl.h>

#include <xf86drm.h>

#define DRI_DEVICE_NODE "/dev/dri/card0"

int main()
{
    int drm_fd, rc, err;

    drm_fd = open(DRI_DEVICE_NODE, O_RDWR | FD_CLOEXEC);
    assert(drm_fd != -1);

    rc = drmSetClientCap(drm_fd, DRM_CLIENT_CAP_ATOMIC, 1);

    /* Errno can be overwritten so save it immediately */
    err = errno;

    printf("drmSetClientCap(%d, DRM_CLIENT_CAP_ATOMIC, 1) = %d\n", drm_fd, rc);
    if (rc < 0)
    {
        printf("errno = %d\n", err);
    }
}