Add the wait6(2) system call. It takes POSIX waitid()-like process

designator to select a process which is waited for. The system call
optionally returns siginfo_t which would be otherwise provided to
SIGCHLD handler, as well as extended structure accounting for child
and cumulative grandchild resource usage.

Allow to get the current rusage information for non-exited processes
as well, similar to Solaris.

The explicit WEXITED flag is required to wait for exited processes,
allowing for more fine-grained control of the events the waiter is
interested in.

Fix the handling of siginfo for WNOWAIT option for all wait*(2)
family, by not removing the queued signal state.

PR:	standards/170346
Submitted by:	"Jukka A. Ukkonen" <jau@iki.fi>
MFC after:	1 month

1 files changed, 5 insertions, 2 deletions

diff --git a/sys/kern/syscalls.master b/sys/kern/syscalls.master
index 5cb90f8..148dea3 100644
--- a/sys/kern/syscalls.master
+++ b/sys/kern/syscalls.master
@@ -71,8 +71,7 @@
 ; XXX man page says `mode_t mode'.
 6	AUE_CLOSE	STD	{ int close(int fd); }
 7	AUE_WAIT4	STD	{ int wait4(int pid, int *status, \
-				    int options, struct rusage *rusage); } \
-				    wait4 wait_args int
+				    int options, struct rusage *rusage); }
 8	AUE_CREAT	COMPAT	{ int creat(char *path, int mode); }
 9	AUE_LINK	STD	{ int link(char *path, char *link); }
 10	AUE_UNLINK	STD	{ int unlink(char *path); }
@@ -952,5 +951,9 @@
 				    off_t offset, off_t len); }
 531	AUE_NULL	STD	{ int posix_fadvise(int fd, off_t offset, \
 				    off_t len, int advice); }
+532	AUE_WAIT6	STD	{ int wait6(int idtype, int id, \
+				    int *status, int options, \
+				    struct __wrusage *wrusage, \
+				    siginfo_t *info); }
 ; Please copy any additions and changes to the following compatability tables:
 ; sys/compat/freebsd32/syscalls.master