This is an extension to provide gawk with I/O multiplexing capability.
It currently provides these functions:
   select
   kill
   set_non_blocking
   select_signal
   input_fd
   output_fd
Please refer to the man page, test cases, and included examples multiplex*.awk
for more info.

This extension requires version 2.0 or greater of the gawk API, first available
in gawk version 4.2.0.
