Change Details

The debugger like truss(1) depends on the wait(2) syscall. This syscall waits for ALL children. When it is waiting for ALL child's the children created by process descriptors are not returned. This behavior was introduced because we want to implement libraries which may pdfork(1). The behavior of process descriptor brakes truss(1) because it will not be able to collect the status of processes with process descriptors. To address this problem the status is returned to parent when the child is traced. While the process is traced the debugger is the parent. The new process flag (P2_EXIT_TRACED) is introduced. This flag informs that process exited while being traced. Otherwise, the debugger will not collect the exit code of the traced process. Unfortunately, that is not possible because of the kern_wait6(). This function again reparents the process to the original state. If the P_TRACE flag would be set, the process would be added to the orphan list of the debugger process - which would cause crash. Add test case to verify that. The test case was implemented by markj@.

The debugger like truss(1) depends on the wait(2) syscall. This syscall waits for ALL children. When it is waiting for ALL child's the children created by process descriptors are not returned. This behavior was introduced because we want to implement libraries which may pdfork(1). The behavior of process descriptor brakes truss(1) because it will not be able to collect the status of processes with process descriptors. To address this problem the status is returned to parent when the child is traced. While the process is traced the debugger is the new parent. In case the original parent and debugger are the same process it means the debugger explicitly used pdfork() to create the child. In that case the debugger should be using kqueue()/pdwait() instead of wait(). Add test case to verify that. The test case was implemented by markj@.

The debugger like truss(1) depends on the wait(2) syscall. This syscall waits for ALL children. When it is waiting for ALL child's the children created by process descriptors are not returned. This behavior was introduced because we want to implement libraries which may pdfork(1). The behavior of process descriptor brakes truss(1) because it will not be able to collect the status of processes with process descriptors. To address this problem the status is returned to parent when the child is traced. While the process is traced the debugger is the parent. The new process flag (P2_EXIT_TRACED) is introducedarent. This flag informs that process exited while being traced.In case the original parent and debugger are the same process it means the Otherwise, the debugger will not collect the exit code of the traced process. Unfortunately,explicitly used pdfork() to create the child. that is not possible because ofIn that case the kern_wait6().debugger This function again reparents the process to the original state. If the P_TRACE flag would be set, the process would be added to the orphan list of the debugger process - which would cause crashshould be using kqueue()/pdwait() instead of wait(). Add test case to verify that. The test case was implemented by markj@.