Similar to 233760 and 236717, export some more useful info about the

kernel-based POSIX semaphore descriptors to userland via procstat(1) and
fstat(1):
- Change sem file descriptors to track the pathname they are associated
  with and add a ksem_info() method to copy the path out to a
  caller-supplied buffer.
- Use the fo_stat() method of shared memory objects and ksem_info() to
  export the path, mode, and value of a semaphore via struct kinfo_file.
- Add a struct semstat to the libprocstat(3) interface along with a
  procstat_get_sem_info() to export the mode and value of a semaphore.
- Teach fstat about semaphores and to display their path, mode, and value.

MFC after:	2 weeks

1 files changed, 2 insertions, 0 deletions

diff --git a/usr.bin/fstat/fstat.1 b/usr.bin/fstat/fstat.1
index 7403a8e..268b70f 100644
--- a/usr.bin/fstat/fstat.1
+++ b/usr.bin/fstat/fstat.1
@@ -155,6 +155,8 @@ using a symbolic format (see
 otherwise, the mode is printed
 as an octal number.
 .It Li SZ\&|DV
+If the file is a semaphore,
+prints the current value of the semaphore.
 If the file is not a character or block special, prints the size of
 the file in bytes.
 Otherwise, if the