| // +build linux |
| |
| // Package sys provides access to the Get Child and Set Child prctl flags. |
| // See http://man7.org/linux/man-pages/man2/prctl.2.html |
| package sys |
| |
| import ( |
| "unsafe" |
| |
| "golang.org/x/sys/unix" |
| ) |
| |
| // GetSubreaper returns the subreaper setting for the calling process |
| func GetSubreaper() (int, error) { |
| var i uintptr |
| // PR_GET_CHILD_SUBREAPER allows retrieving the current child |
| // subreaper. |
| // Returns the "child subreaper" setting of the caller, in the |
| // location pointed to by (int *) arg2. |
| if err := unix.Prctl(unix.PR_GET_CHILD_SUBREAPER, uintptr(unsafe.Pointer(&i)), 0, 0, 0); err != nil { |
| return -1, err |
| } |
| return int(i), nil |
| } |
| |
| // SetSubreaper sets the value i as the subreaper setting for the calling process |
| func SetSubreaper(i int) error { |
| // PR_SET_CHILD_SUBREAPER allows setting the child subreaper. |
| // If arg2 is nonzero, set the "child subreaper" attribute of the |
| // calling process; if arg2 is zero, unset the attribute. When a |
| // process is marked as a child subreaper, all of the children |
| // that it creates, and their descendants, will be marked as |
| // having a subreaper. In effect, a subreaper fulfills the role |
| // of init(1) for its descendant processes. Upon termination of |
| // a process that is orphaned (i.e., its immediate parent has |
| // already terminated) and marked as having a subreaper, the |
| // nearest still living ancestor subreaper will receive a SIGCHLD |
| // signal and be able to wait(2) on the process to discover its |
| // termination status. |
| return unix.Prctl(unix.PR_SET_CHILD_SUBREAPER, uintptr(i), 0, 0, 0) |
| } |