cmake HAVE_V4L2 examples

webcamoid/webcamoid libAvKys/Plugins/VideoCapture/src/capture/v4l2sys/CMakeLists.txt :56 

check_cxx_source_compiles("
#include <linux/videodev2.h>

int main()
{
    return 0;
}" HAVE_V4L2)

webcamoid/webcamoid libAvKys/Plugins/VideoCapture/src/capture/v4lutils/CMakeLists.txt :57 

check_cxx_source_compiles("
#include <linux/videodev2.h>

int main()
{
    return 0;
}" HAVE_V4L2)

webcamoid/webcamoid libAvKys/Plugins/VirtualCamera/src/akvcam/CMakeLists.txt :55 

check_cxx_source_compiles("
#include <linux/videodev2.h>

int main()
{
    return 0;
}" HAVE_V4L2)

webcamoid/webcamoid libAvKys/Plugins/VirtualCamera/src/v4l2lb/CMakeLists.txt :56 

check_cxx_source_compiles("
#include <linux/videodev2.h>

int main()
{
    return 0;
}" HAVE_V4L2)

letoram/arcan src/frameserver/encode/default/CMakeLists.txt :121 

list(APPEND ENCODE_DEFS HAVE_V4L2)

TheImagingSource/tiscamera src/CMakeLists.txt :170 

target_compile_definitions(tcam PRIVATE -DHAVE_V4L2)