is specified as NULL, then
.BR ppoll ()
can block indefinitely.
-.SH "RETURN VALUE"
+.SH RETURN VALUE
On success, a positive number is returned; this is
the number of structures which have nonzero
.I revents
The
.BR ppoll ()
library call was added in glibc 2.4.
-.SH "CONFORMING TO"
+.SH CONFORMING TO
.BR poll ()
conforms to POSIX.1-2001.
.BR ppoll ()
See the discussion of spurious readiness notifications under the
BUGS section of
.BR select (2).
-.SH "SEE ALSO"
+.SH SEE ALSO
.BR select (2),
.BR select_tut (2),
.BR time (7)