Define eventfd on NetBSD

Like FreeBSD, NetBSD supports eventfd, see
https://man.netbsd.org/eventfd.2.
OpenBSD does not AFAICT.

While at, it make the already define eventfd* argument names match
the respective OSs man pages (or header files).

Author: krobelus

src/fuchsia/mod.rs

@@ -3918,7 +3918,7 @@ extern "C" {
         len: size_t,
         flags: c_uint,
     ) -> ssize_t;
-    pub fn eventfd(init: c_uint, flags: c_int) -> c_int;
+    pub fn eventfd(initval: c_uint, flags: c_int) -> c_int;
     pub fn sched_rr_get_interval(pid: crate::pid_t, tp: *mut crate::timespec) -> c_int;
     pub fn sem_timedwait(sem: *mut sem_t, abstime: *const crate::timespec) -> c_int;
     pub fn sem_getvalue(sem: *mut sem_t, sval: *mut c_int) -> c_int;

src/unix/bsd/freebsdlike/freebsd/mod.rs

@@ -4700,7 +4700,7 @@ extern "C" {
     pub fn memfd_create(name: *const c_char, flags: c_uint) -> c_int;
     pub fn setaudit(auditinfo: *const auditinfo_t) -> c_int;
 
-    pub fn eventfd(init: c_uint, flags: c_int) -> c_int;
+    pub fn eventfd(initval: c_uint, flags: c_int) -> c_int;
     pub fn eventfd_read(fd: c_int, value: *mut eventfd_t) -> c_int;
     pub fn eventfd_write(fd: c_int, value: eventfd_t) -> c_int;
 

src/unix/bsd/netbsdlike/netbsd/mod.rs

@@ -7,6 +7,7 @@ use crate::{
 };
 
 pub type blksize_t = i32;
+pub type eventfd_t = u64;
 pub type fsblkcnt_t = u64;
 pub type fsfilcnt_t = u64;
 pub type idtype_t = c_int;
@@ -1742,6 +1743,11 @@ pub const RTA_TAG: c_int = 0x100;
 pub const RTAX_TAG: c_int = 8;
 pub const RTAX_MAX: c_int = 9;
 
+// For eventfd
+pub const EFD_SEMAPHORE: c_int = crate::O_RDWR;
+pub const EFD_NONBLOCK: c_int = crate::O_NONBLOCK;
+pub const EFD_CLOEXEC: c_int = crate::O_CLOEXEC;
+
 // sys/timerfd.h
 pub const TFD_CLOEXEC: i32 = crate::O_CLOEXEC;
 pub const TFD_NONBLOCK: i32 = crate::O_NONBLOCK;
@@ -2197,6 +2203,10 @@ extern "C" {
     pub fn getmntinfo(mntbufp: *mut *mut crate::statvfs, flags: c_int) -> c_int;
     pub fn getvfsstat(buf: *mut crate::statvfs, bufsize: size_t, flags: c_int) -> c_int;
 
+    pub fn eventfd(val: c_uint, flags: c_int) -> c_int;
+    pub fn eventfd_read(efd: c_int, valp: *mut eventfd_t) -> c_int;
+    pub fn eventfd_write(efd: c_int, val: eventfd_t) -> c_int;
+
     // Added in `NetBSD` 10.0
     pub fn timerfd_create(clockid: crate::clockid_t, flags: c_int) -> c_int;
     pub fn timerfd_gettime(fd: c_int, curr_value: *mut crate::itimerspec) -> c_int;

src/unix/linux_like/android/mod.rs

@@ -3526,7 +3526,7 @@ extern "C" {
         len: size_t,
         flags: c_uint,
     ) -> ssize_t;
-    pub fn eventfd(init: c_uint, flags: c_int) -> c_int;
+    pub fn eventfd(initval: c_uint, flags: c_int) -> c_int;
     pub fn eventfd_read(fd: c_int, value: *mut eventfd_t) -> c_int;
     pub fn eventfd_write(fd: c_int, value: eventfd_t) -> c_int;
     pub fn sched_rr_get_interval(pid: crate::pid_t, tp: *mut crate::timespec) -> c_int;

src/unix/linux_like/linux/mod.rs

@@ -6088,7 +6088,7 @@ extern "C" {
         len: size_t,
         flags: c_uint,
     ) -> ssize_t;
-    pub fn eventfd(init: c_uint, flags: c_int) -> c_int;
+    pub fn eventfd(initval: c_uint, flags: c_int) -> c_int;
     pub fn eventfd_read(fd: c_int, value: *mut eventfd_t) -> c_int;
     pub fn eventfd_write(fd: c_int, value: eventfd_t) -> c_int;
 

src/unix/solarish/illumos.rs

@@ -212,7 +212,7 @@ pub const TFD_TIMER_ABSTIME: i32 = 1 << 0;
 pub const TFD_TIMER_CANCEL_ON_SET: i32 = 1 << 1;
 
 extern "C" {
-    pub fn eventfd(init: c_uint, flags: c_int) -> c_int;
+    pub fn eventfd(initval: c_uint, flags: c_int) -> c_int;
 
     pub fn epoll_pwait(
         epfd: c_int,