in src/platform_impl/linux/x11/window.rs [458:496]
fn set_pid(&self) -> Option<util::Flusher<'_>> {
let pid_atom = unsafe { self.xconn.get_atom_unchecked(b"_NET_WM_PID\0") };
let client_machine_atom = unsafe { self.xconn.get_atom_unchecked(b"WM_CLIENT_MACHINE\0") };
unsafe {
// 64 would suffice for Linux, but 256 will be enough everywhere (as per SUSv2). For instance, this is
// the limit defined by OpenBSD.
const MAXHOSTNAMELEN: usize = 256;
// `assume_init` is safe here because the array consists of `MaybeUninit` values,
// which do not require initialization.
let mut buffer: [MaybeUninit<c_char>; MAXHOSTNAMELEN] =
MaybeUninit::uninit().assume_init();
let status = libc::gethostname(buffer.as_mut_ptr() as *mut c_char, buffer.len());
if status != 0 {
return None;
}
ptr::write(buffer[MAXHOSTNAMELEN - 1].as_mut_ptr() as *mut u8, b'\0'); // a little extra safety
let hostname_length = libc::strlen(buffer.as_ptr() as *const c_char);
let hostname = slice::from_raw_parts(buffer.as_ptr() as *const c_char, hostname_length);
self.xconn
.change_property(
self.xwindow,
pid_atom,
ffi::XA_CARDINAL,
util::PropMode::Replace,
&[libc::getpid() as util::Cardinal],
)
.queue();
let flusher = self.xconn.change_property(
self.xwindow,
client_machine_atom,
ffi::XA_STRING,
util::PropMode::Replace,
&hostname[0..hostname_length],
);
Some(flusher)
}
}