diff --git a/lib/std/c/netbsd.zig b/lib/std/c/netbsd.zig
index 7169095197..c988d25a7b 100644
--- a/lib/std/c/netbsd.zig
+++ b/lib/std/c/netbsd.zig
@@ -18,14 +18,14 @@ pub extern "c" fn _lwp_self() lwpid_t;
 
 pub extern "c" fn pipe2(fds: *[2]fd_t, flags: u32) c_int;
 pub extern "c" fn arc4random_buf(buf: [*]u8, len: usize) void;
-pub extern "c" fn __fstat50(fd: fd_t, buf: *Stat) c_int;
-pub extern "c" fn __stat50(path: [*:0]const u8, buf: *Stat) c_int;
+pub extern "c" fn __fstat50(fd: fd_t, buf: *libc_stat) c_int;
+pub extern "c" fn __stat50(path: [*:0]const u8, buf: *libc_stat) c_int;
 pub extern "c" fn __clock_gettime50(clk_id: c_int, tp: *timespec) c_int;
 pub extern "c" fn __clock_getres50(clk_id: c_int, tp: *timespec) c_int;
 pub extern "c" fn __getdents30(fd: c_int, buf_ptr: [*]u8, nbytes: usize) c_int;
 pub extern "c" fn __sigaltstack14(ss: ?*stack_t, old_ss: ?*stack_t) c_int;
 pub extern "c" fn __nanosleep50(rqtp: *const timespec, rmtp: ?*timespec) c_int;
-pub extern "c" fn __sigaction14(sig: c_int, noalias act: *const Sigaction, noalias oact: ?*Sigaction) c_int;
+pub extern "c" fn __sigaction14(sig: c_int, noalias act: ?*const Sigaction, noalias oact: ?*Sigaction) c_int;
 pub extern "c" fn __sigprocmask14(how: c_int, noalias set: ?*const sigset_t, noalias oset: ?*sigset_t) c_int;
 pub extern "c" fn __socket30(domain: c_uint, sock_type: c_uint, protocol: c_uint) c_int;
 pub extern "c" fn __gettimeofday50(noalias tv: ?*timeval, noalias tz: ?*timezone) c_int;
@@ -34,7 +34,6 @@ pub extern "c" fn __getrusage50(who: c_int, usage: *rusage) c_int;
 pub extern "c" fn __libc_thr_yield() c_int;
 
 pub extern "c" fn posix_memalign(memptr: *?*c_void, alignment: usize, size: usize) c_int;
-pub extern "c" fn malloc_usable_size(?*const c_void) usize;
 
 pub const pthread_mutex_t = extern struct {
     ptm_magic: u32 = 0x33330003,
@@ -93,3 +92,5 @@ pub const pthread_attr_t = extern struct {
     pta_flags: i32,
     pta_private: ?*c_void,
 };
+
+pub const sem_t = ?*opaque {};
diff --git a/lib/std/os/bits/netbsd.zig b/lib/std/os/bits/netbsd.zig
index 57ae70ddbf..dfb6c3bdf9 100644
--- a/lib/std/os/bits/netbsd.zig
+++ b/lib/std/os/bits/netbsd.zig
@@ -813,10 +813,6 @@ pub const sigset_t = extern struct {
     __bits: [_SIG_WORDS]u32,
 };
 
-pub const SIG_ERR = @intToPtr(?Sigaction.sigaction_fn, maxInt(usize));
-pub const SIG_DFL = @intToPtr(?Sigaction.sigaction_fn, 0);
-pub const SIG_IGN = @intToPtr(?Sigaction.sigaction_fn, 1);
-
 pub const empty_sigset = sigset_t{ .__bits = [_]u32{0} ** _SIG_WORDS };
 
 // XXX x86_64 specific
@@ -1219,3 +1215,25 @@ pub const rlimit = extern struct {
 pub const SHUT_RD = 0;
 pub const SHUT_WR = 1;
 pub const SHUT_RDWR = 2;
+
+pub const nfds_t = u32;
+
+pub const pollfd = extern struct {
+    fd: fd_t,
+    events: i16,
+    revents: i16,
+};
+
+/// Testable events (may be specified in events field).
+pub const POLLIN = 0x0001;
+pub const POLLPRI = 0x0002;
+pub const POLLOUT = 0x0004;
+pub const POLLRDNORM = 0x0040;
+pub const POLLWRNORM = POLLOUT;
+pub const POLLRDBAND = 0x0080;
+pub const POLLWRBAND = 0x0100;
+
+/// Non-testable events (may not be specified in events field).
+pub const POLLERR = 0x0008;
+pub const POLLHUP = 0x0010;
+pub const POLLNVAL = 0x0020;