Closed
Description
| Previous ID | SR-4201 |
| Radar | None |
| Original Reporter | @weissi |
| Type | Bug |
| Status | Resolved |
| Resolution | Done |
Attachment: Download
Additional Detail from JIRA
| Votes | 0 |
| Component/s | libdispatch |
| Labels | Bug |
| Assignee | dgrove-oss (JIRA) |
| Priority | Medium |
md5: cb7e513f2c891ab499ed2e68f4d8a5f4
Issue Description:
Description
Signals don't get delivered on `DispatchSourceSignal` on Linux. As a repro, run the following program
#if os(Linux)
import Glibc
#else
import Darwin
#endif
import Dispatch
let sig = SIGCHLD
signal(sig, SIG_IGN);
let q = DispatchQueue(label: "foo")
let s = DispatchSource.makeSignalSource(signal: sig, queue: q)
s.setEventHandler {
print("SIGNAL")
fputs("SIGNAL!\n", stderr)
kill(getpid(), SIGKILL)
}
s.setRegistrationHandler {
print("registered in pid \(getpid())")
print("kill -\(sig) \(getpid())")
}
s.resume()
dispatchMain()and then execute the line that it writes ("kill -...")
on macOS
$ ./test &
[1] 49783
registered in pid 49783
kill -20 49783
$ kill -20 49783
SIGNAL
SIGNAL!
[1]+ Killed: 9 ./test
$
as expected, the program prints "SIGNAL", then "SIGNAL!" and then kills itself.
On Linux
$ ./test &
[1] 28406
registered in pid 28406
kill -17 28406
$ kill -17 28406
$ kill -17 28406
$ kill -17 28406
$ kill -17 28406
and nothing happens, the program is still alive. Interestingly, in LLDB on Linux is sometimes does receive the signal
On Linux in LLDB
$ lldb ./test
(lldb) target create "./test"
Current executable set to './test' (x86_64).
(lldb) run
Process 28461 launched: './test' (x86_64)
registered in pid 28461
kill -17 28461
Process 28461 stopped and restarted: thread 1 received signal: SIGCHLD
SIGNAL
SIGNAL!
Process 28461 exited with status = 9 (0x00000009)
(lldb)
(the kill was run from some other terminal here).
Swift versions:
macOS
$ swiftc --version
Apple Swift version 3.0.2 (swiftlang-800.0.63 clang-800.0.42.1)
Target: x86_64-apple-macosx10.9
Linux
swiftc --version
Swift version 3.0.2 (swift-3.0.2-RELEASE)
Target: x86_64-unknown-linux-gnu
but this also happens with this Swift version
swiftc --version
Swift version 3.1-dev (LLVM 5c165fb715, Clang e540ba0c30, Swift 3d3fdecbb4)
Target: x86_64-unknown-linux-gnu
which is master from 1st Feb 2017