BUG: When more than one command is given and one of them fails to start and the rest are killed, do not forget to reap the killed children.

BUG: struct timeval uses unsigned types on at least one platform (QNX).  Alot of the time logic assumes a signed type.  Switch to using a signed representation that is converted to the native representation only for system calls.

BUG: When killing a child all the pipe read ends should be closed.  This will allow a child that is blocking while waiting to write to the pipe to wake up and receive the kill signal properly on cygwin.

COMP: Adding work-around for CMake dependency scanning limitation.  Any configured header included by KWSYS_HEADER() in a .c or .cxx file in kwsys itself must use this hack to get dependencies.

ENH: Do kwsys testing as part of cmake testing, command line arguments are not experimental and add simple test for systemtools

BUG: Do not disown if process has already been killed or the timeout expired.  Also need to call kwsysProcessCleanup to disown.

ENH: Added kwsysProcess_Disown an kwsysProcess_Option_Detach to allow detached processes to be created.  Currently implemented only on UNIX.

ENH: Added GetExceptionString method to provide an error description when GetState returns Exception.

ENH: Added SetPipeShared method to allow stdout and stderr pipes to be shared with the parent process.

ENH: Added SetPipeFile method to allow the process pipeline stdin, stdout, and stderr to be redirected from/to files.

ENH: Removed pipe selection argument from WaitForData method in kwsysProcess.  This greatly simplifies its use.

ERR: Some platforms define stdin, stdout, and stderr as macros.  Renaming these symbols to StdIn, StdOut, and StdErr.

BUG: When a child fails to exec, we need to read the entire error message, not just the first block.