}
#if defined(sun) && !defined(USG5_4)
else if (nfds > 0 && FD_ISSET (0, &Available) && interrupt_input)
- /* System sometimes fails to deliver SIGIO. */
+ /* System sometimes fails to deliver SIGIO.
+
+ David J. Mackenzie says that Emacs doesn't compile under
+ Solaris if this code is enabled, thus the USG5_4 in the CPP
+ conditional. "I haven't noticed any ill effects so far.
+ If you find a Solaris expert somewhere, they might know
+ better." */
kill (getpid (), SIGIO);
#endif