diff --git a/src/header/signal/mod.rs b/src/header/signal/mod.rs
index f3b970c834..d0fe9fef83 100644
--- a/src/header/signal/mod.rs
+++ b/src/header/signal/mod.rs
@@ -24,6 +24,7 @@ type SigSet = BitSet<[c_ulong; 1]>;
 pub const SIG_DFL: usize = 0;
 pub const SIG_IGN: usize = 1;
 pub const SIG_ERR: isize = -1;
+pub const SIG_HOLD: isize = 2;
 
 pub const SIG_BLOCK: c_int = 0;
 pub const SIG_UNBLOCK: c_int = 1;
@@ -231,14 +232,18 @@ pub extern "C" fn signal(
     unsafe { old_sa.assume_init() }.sa_handler
 }
 
-// #[no_mangle]
-pub extern "C" fn sigpause(sig: c_int) -> c_int {
-    unimplemented!();
+#[no_mangle]
+pub unsafe extern "C" fn sigpause(sig: c_int) -> c_int {
+    let mut pset = mem::MaybeUninit::<sigset_t>::uninit();
+    sigprocmask(0, ptr::null_mut(), pset.as_mut_ptr());
+    let mut set = pset.assume_init();
+    sigdelset(&mut set, sig);
+    sigsuspend(&mut set)
 }
 
-// #[no_mangle]
+#[no_mangle]
 pub extern "C" fn sigpending(set: *mut sigset_t) -> c_int {
-    unimplemented!();
+    Sys::sigpending(set)
 }
 
 #[no_mangle]
@@ -246,19 +251,61 @@ pub extern "C" fn sigprocmask(how: c_int, set: *const sigset_t, oset: *mut sigse
     Sys::sigprocmask(how, set, oset)
 }
 
-// #[no_mangle]
-pub extern "C" fn sigrelse(sig: c_int) -> c_int {
-    unimplemented!();
+#[no_mangle]
+pub unsafe extern "C" fn sigrelse(sig: c_int) -> c_int {
+    let mut pset = mem::MaybeUninit::<sigset_t>::uninit();
+    sigemptyset(pset.as_mut_ptr());
+    let mut set = pset.assume_init();
+    if sigaddset(&mut set, sig) < 0 {
+        return -1;
+    }
+    sigprocmask(SIG_UNBLOCK, &mut set, ptr::null_mut())
 }
 
-// #[no_mangle]
-pub extern "C" fn sigset(sig: c_int, func: fn(c_int)) -> fn(c_int) {
-    unimplemented!();
+#[no_mangle]
+pub unsafe extern "C" fn sigset(
+    sig: c_int,
+    func: Option<extern "C" fn(c_int)>
+) -> Option<extern "C" fn(c_int)> {
+    let mut old_sa = mem::MaybeUninit::uninit();
+    let mut pset = mem::MaybeUninit::<sigset_t>::uninit();
+    let sig_hold: Option<extern "C" fn(c_int)> = mem::transmute(SIG_HOLD);
+    let sig_err: Option<extern "C" fn(c_int)> = mem::transmute(SIG_ERR);
+    sigemptyset(pset.as_mut_ptr());
+    let mut set = pset.assume_init();
+    if sigaddset(&mut set, sig) < 0 {
+        return sig_err;
+    } else {
+        if func == sig_hold {
+            if sigaction(sig, ptr::null_mut(), old_sa.as_mut_ptr()) < 0 ||
+               sigprocmask(SIG_BLOCK, &mut set, &mut set) < 0 {
+                   mem::forget(old_sa);
+                   return sig_err;
+            }
+        } else {
+            let mut sa = sigaction {
+                sa_handler: func,
+                sa_flags: 0 as c_ulong,
+                sa_restorer: Some(__restore_rt),
+                sa_mask: sigset_t::default(),
+            };
+            sigemptyset(&mut sa.sa_mask);
+            if sigaction(sig, &sa, old_sa.as_mut_ptr()) < 0 ||
+               sigprocmask(SIG_UNBLOCK, &mut set, &mut set) < 0 {
+                   mem::forget(old_sa);
+                   return sig_err;
+            }
+        }
+    }
+    if sigismember(&mut set, sig) == 1 {
+        return sig_hold;
+    }
+    old_sa.assume_init().sa_handler
 }
 
-// #[no_mangle]
+#[no_mangle]
 pub extern "C" fn sigsuspend(sigmask: *const sigset_t) -> c_int {
-    unimplemented!();
+    Sys::sigsuspend(sigmask)
 }
 
 // #[no_mangle]
diff --git a/src/platform/linux/signal.rs b/src/platform/linux/signal.rs
index d8bf311c62..c0ab260539 100644
--- a/src/platform/linux/signal.rs
+++ b/src/platform/linux/signal.rs
@@ -5,7 +5,7 @@ use super::{
     e, Sys,
 };
 use crate::header::{
-    signal::{sigaction, sigset_t, stack_t},
+    signal::{NSIG, sigaction, sigset_t, stack_t},
     sys_time::itimerval,
 };
 
@@ -51,7 +51,15 @@ impl PalSignal for Sys {
         e(unsafe { syscall!(SIGALTSTACK, ss, old_ss) }) as c_int
     }
 
+    fn sigpending(set: *mut sigset_t) -> c_int {
+        e(unsafe { syscall!(RT_SIGPENDING, set, NSIG/8) }) as c_int
+    }
+
     fn sigprocmask(how: c_int, set: *const sigset_t, oset: *mut sigset_t) -> c_int {
         e(unsafe { syscall!(RT_SIGPROCMASK, how, set, oset, mem::size_of::<sigset_t>()) }) as c_int
     }
+
+    fn sigsuspend(set: *const sigset_t) -> c_int {
+        e(unsafe { syscall!(RT_SIGSUSPEND, set, NSIG/8) }) as c_int
+    }
 }
diff --git a/src/platform/pal/signal.rs b/src/platform/pal/signal.rs
index b432f57922..a91c69d8c6 100644
--- a/src/platform/pal/signal.rs
+++ b/src/platform/pal/signal.rs
@@ -19,5 +19,9 @@ pub trait PalSignal: Pal {
 
     fn sigaltstack(ss: *const stack_t, old_ss: *mut stack_t) -> c_int;
 
+    fn sigpending(set: *mut sigset_t) -> c_int;
+
     fn sigprocmask(how: c_int, set: *const sigset_t, oset: *mut sigset_t) -> c_int;
+
+    fn sigsuspend(set: *const sigset_t) -> c_int;
 }
diff --git a/src/platform/redox/signal.rs b/src/platform/redox/signal.rs
index 801d947d95..ebbea5f2b7 100644
--- a/src/platform/redox/signal.rs
+++ b/src/platform/redox/signal.rs
@@ -7,7 +7,7 @@ use super::{
 };
 use crate::{
     header::{
-        errno::EINVAL,
+        errno::{EINVAL, ENOSYS},
         signal::{sigaction, sigset_t, stack_t},
         sys_time::{itimerval, ITIMER_REAL},
     },
@@ -135,6 +135,11 @@ impl PalSignal for Sys {
         unimplemented!()
     }
 
+    fn sigpending(set: *mut sigset_t) -> c_int {
+        platform::errno = ENOSYS;
+        -1
+    }
+
     fn sigprocmask(how: c_int, set: *const sigset_t, oset: *mut sigset_t) -> c_int {
         let new_opt = if set.is_null() {
             None
@@ -152,4 +157,9 @@ impl PalSignal for Sys {
         }
         ret
     }
+
+    fn sigsuspend(set: *const sigset_t) -> c_int {
+        platform::errno = ENOSYS;
+        -1
+    }
 }