cmake ZMQ_HAVE_O_CLOEXEC examples

zeromq/libzmq builds/cmake/Modules/ZMQSourceRunChecks.cmake :36 

check_c_source_runs(
    "
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

int main(int argc, char *argv [])
{
    int s = open (\"/dev/null\", O_CLOEXEC | O_RDONLY);
    return s == -1;
}
"
    ZMQ_HAVE_O_CLOEXEC)

asset-group/5ghoul-5g-nr-attacks libs/libzmq/builds/cmake/Modules/ZMQSourceRunChecks.cmake :36 

check_c_source_runs(
    "
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

int main(int argc, char *argv [])
{
    int s = open (\"/dev/null\", O_CLOEXEC | O_RDONLY);
    return s == -1;
}
"
    ZMQ_HAVE_O_CLOEXEC)