[Asterisk-Dev] channel fds question

[Luigi Rizzo]

another channel question -- i see there is room for
AST_MAX_FDS file descriptors, i notice the upper two
are normally used (reserved ?) for the alertpipe and timingfd,
but are there others that are 'reserved' ?
 
Specifically, i would like to support 'generator' apps which
come from a source that is already more or less synchronous
without requiring the timingfd. Can I use, in 
ast_settimeout(), AST_MAX_FDS-3 for that ?
Or any descriptor that i find set to -1 ?
 
        cheers
        luigi