diff options
Diffstat (limited to 'src/sys/wait.rs')
| -rw-r--r-- | src/sys/wait.rs | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/src/sys/wait.rs b/src/sys/wait.rs index 7033422d..f31f666d 100644 --- a/src/sys/wait.rs +++ b/src/sys/wait.rs @@ -40,16 +40,56 @@ libc_bitflags!( target_os = "android"))] const WSTOPPED: WaitPidFlag = WUNTRACED; +/// Possible return values from `wait()` or `waitpid()`. +/// +/// Each status (other than `StillAlive`) describes a state transition +/// in a child process `Pid`, such as the process exiting or stopping, +/// plus additional data about the transition if any. +/// +/// Note that there are two Linux-specific enum variants, `PtraceEvent` +/// and `PtraceSyscall`. Portable code should avoid exhaustively +/// matching on `WaitStatus`. #[derive(Eq, PartialEq, Clone, Copy, Debug)] pub enum WaitStatus { + /// The process exited normally (as with `exit()` or returning from + /// `main`) with the given exit code. This case matches the C macro + /// `WIFEXITED(status)`; the second field is `WEXITSTATUS(status)`. Exited(Pid, i8), + /// The process was killed by the given signal. The third field + /// indicates whether the signal generated a core dump. This case + /// matches the C macro `WIFSIGNALED(status)`; the last two fields + /// correspond to `WTERMSIG(status)` and `WCOREDUMP(status)`. Signaled(Pid, Signal, bool), + /// The process is alive, but was stopped by the given signal. This + /// is only reported if `WaitPidFlag::WUNTRACED` was passed. This + /// case matches the C macro `WIFSTOPPED(status)`; the second field + /// is `WSTOPSIG(status)`. Stopped(Pid, Signal), + /// The traced process was stopped by a `PTRACE_EVENT_*` event. See + /// [`nix::sys::ptrace`] and [`ptrace`(2)] for more information. All + /// currently-defined events use `SIGTRAP` as the signal; the third + /// field is the `PTRACE_EVENT_*` value of the event. + /// + /// [`nix::sys::ptrace`]: ../ptrace/index.html + /// [`ptrace`(2)]: http://man7.org/linux/man-pages/man2/ptrace.2.html #[cfg(any(target_os = "linux", target_os = "android"))] PtraceEvent(Pid, Signal, c_int), + /// The traced process was stopped by execution of a system call, + /// and `PTRACE_O_TRACESYSGOOD` is in effect. See [`ptrace`(2)] for + /// more information. + /// + /// [`ptrace`(2)]: http://man7.org/linux/man-pages/man2/ptrace.2.html #[cfg(any(target_os = "linux", target_os = "android"))] PtraceSyscall(Pid), + /// The process was previously stopped but has resumed execution + /// after receiving a `SIGCONT` signal. This is only reported if + /// `WaitPidFlag::WCONTINUED` was passed. This case matches the C + /// macro `WIFCONTINUED(status)`. Continued(Pid), + /// There are currently no state changes to report in any awaited + /// child process. This is only returned if `WaitPidFlag::WNOHANG` + /// was used (otherwise `wait()` or `waitpid()` would block until + /// there was something to report). StillAlive } |