add LockOSThread and UnlockOSThread to
runtime package for use by debugger,
which needs to make sure that all ptrace calls
about a given pid come from the same thread.

R=r
DELTA=175  (90 added, 63 deleted, 22 changed)
OCL=31546
CL=31558
3 files changed
tree: 1f8296c92fdb3c4c5c200b360ca1603565e8cc5a
  1. doc/
  2. include/
  3. lib/
  4. misc/
  5. pkg/
  6. src/
  7. test/
  8. usr/