POSIX.1 doesn't define ut_host in struct utmpx. Also, Linux has support
for an exit status value in ut_exit. This commit adds conditional code
for both ut_host and ut_exit to maximise portability.
- renamed the two files, including the header was conflicting with official headers
- configure look for utmp/utmpx headers, wo we know which struct to use
- reworked the usage for linux, works mostly (last still showing 'gone' for loggued users)
The top level socket directory is now called XRDP_SOCKET_ROOT_PATH.
Below that are user-specific directories referred to with the
XRDP_SOCKET_PATH macro - this name is hard-coded into xorgxrdp and
the audio modules as an environment variable.
XRDP_SOCKET_PATH now looks like $XRDP_SOCKET_ROOT_PATH/<uid>
XRDP_SOCKET_PATH is only writeable by the user, and readable by the user
and the xrdp process.
This allows Linux's no_new_privs restriction to be disabled when starting
the X server, which may be desirable if xrdp is running inside a kernel
confinement framework such as AppArmor or SELinux.
env.c : The value of XRDP_SESSION in the environment is now set to the
PID of the sesexec process, which ties up the session with the
output of "xrdp-sesadmin -c=list".
Later versions of xrdp-sesadmin can use this value to get
information about the current process.
matt335672