From ef4550cd6947f56056512126b4d3a3f32932bdc4 Mon Sep 17 00:00:00 2001
From: Xu Shaohua <shaohua@biofan.org>
Date: Mon, 5 Aug 2024 14:06:52 +0800
Subject: [PATCH] readme: Handle alarm signal

---
 README.md         | 23 +++++++++++++++++++++++
 examples/alarm.rs |  6 ------
 src/lib.rs        | 23 +++++++++++++++++++++++
 3 files changed, 46 insertions(+), 6 deletions(-)

diff --git a/README.md b/README.md
index 09c6a9e8..864ab296 100644
--- a/README.md
+++ b/README.md
@@ -69,6 +69,29 @@ let ret = unsafe { nc::kill(pid, nc::SIGTERM) };
 println!("ret: {:?}", ret);
 ```
 
+Or handle signals:
+```rust
+fn handle_alarm(signum: i32) {
+    assert_eq!(signum, nc::SIGALRM);
+}
+
+fn main() {
+    let sa = nc::sigaction_t {
+        sa_handler: handle_alarm as nc::sighandler_t,
+        sa_flags: nc::SA_RESTORER,
+        sa_restorer: nc::restore::get_sa_restorer(),
+        ..nc::sigaction_t::default()
+    };
+    let ret = unsafe { nc::rt_sigaction(nc::SIGALRM, Some(&sa), None) };
+    assert!(ret.is_ok());
+    let remaining = unsafe { nc::alarm(1) };
+    let ret = unsafe { nc::pause() };
+    assert!(ret.is_err());
+    assert_eq!(ret, Err(nc::EINTR));
+    assert_eq!(remaining, 0);
+}
+```
+
 ## Stable version
 
 For stable version of rustc, please install a C compiler (`gcc` or `clang`) first.
diff --git a/examples/alarm.rs b/examples/alarm.rs
index d8f9d119..862370eb 100644
--- a/examples/alarm.rs
+++ b/examples/alarm.rs
@@ -48,15 +48,9 @@ fn main() {
 
     let seconds = 1;
     let remaining = alarm(seconds);
-
     let mask = nc::sigset_t::default();
     let ret = unsafe { nc::rt_sigsuspend(&mask) };
     assert!(ret.is_err());
     assert_eq!(ret, Err(nc::EINTR));
-
     assert_eq!(remaining.unwrap(), 0);
-
-    unsafe {
-        nc::exit(1);
-    }
 }
diff --git a/src/lib.rs b/src/lib.rs
index 03ae8263..68bdeeaa 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -55,6 +55,29 @@
 //! assert_eq!(ret, Err(nc::EPERM));
 //! ```
 //!
+//! Or handle signals:
+//! ```
+//! fn handle_alarm(signum: i32) {
+//!     assert_eq!(signum, nc::SIGALRM);
+//! }
+//!
+//! fn main() {
+//!     let sa = nc::sigaction_t {
+//!         sa_handler: handle_alarm as nc::sighandler_t,
+//!         sa_flags: nc::SA_RESTORER,
+//!         sa_restorer: nc::restore::get_sa_restorer(),
+//!         ..nc::sigaction_t::default()
+//!     };
+//!     let ret = unsafe { nc::rt_sigaction(nc::SIGALRM, Some(&sa), None) };
+//!     assert!(ret.is_ok());
+//!     let remaining = unsafe { nc::alarm(1) };
+//!     let ret = unsafe { nc::pause() };
+//!     assert!(ret.is_err());
+//!     assert_eq!(ret, Err(nc::EINTR));
+//!     assert_eq!(remaining, 0);
+//! }
+//! ```
+//!
 //! Or get system info:
 //! ```rust
 //! pub fn cstr_to_str(input: &[u8]) -> &str {