doc: Add document for killpg

DanSnow · DanSnow · commit e53ccf556cf4 · 2019-03-05T18:39:15.000+08:00
diff --git a/src/sys/signal.rs b/src/sys/signal.rs
@@ -680,6 +680,8 @@ pub fn kill<T: Into<Option<Signal>>>(pid: ::unistd::Pid, signal: T) -> Result<()
     Errno::result(res).map(drop)
 }
 
+/// Send a signal to a process group [(see
+/// killpg(3))](http://pubs.opengroup.org/onlinepubs/9699919799/functions/killpg.html).
 pub fn killpg<T: Into<Option<Signal>>>(pid: ::unistd::Pid, signal: T) -> Result<()> {
     let res = unsafe { libc::killpg(pid.into(),
                                   match signal.into() {

Original file line number	Diff line number	Diff line change
`@@ -680,6 +680,8 @@ pub fn kill<T: Into<Option<Signal>>>(pid: ::unistd::Pid, signal: T) -> Result<()`
`680`	`680`	`Errno::result(res).map(drop)`
`681`	`681`	`}`
`682`	`682`
	`683`	`+/// Send a signal to a process group [(see`
	`684`	`+/// killpg(3))](http://pubs.opengroup.org/onlinepubs/9699919799/functions/killpg.html).`
`683`	`685`	`pub fn killpg<T: Into<Option<Signal>>>(pid: ::unistd::Pid, signal: T) -> Result<()> {`
`684`	`686`	`let res = unsafe { libc::killpg(pid.into(),`
`685`	`687`	`match signal.into() {`