'\" te
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.TH TIMERFD 5 "Feb 23, 2015"
.SH NAME
timerfd \- Linux-compatible timer notification facility
.SH SYNOPSIS

.LP
.nf
#include <sys/timerfd.h>
.fi

.SH DESCRIPTION
.sp
.LP

\fBtimerfd\fR is a Linux-borne facility for creating POSIX timers and
receiving their subsequent events via a file descriptor.
The facility itself is arguably unnecessary:
portable code can either use the timeout value present in 
\fBpoll\fR(2)/\fBport_get\fR(3C)/\fBepoll_wait\fR(3C) or -- if this
is deemed of unacceptably poor resolution -- create a POSIX timer
via \fBtimer_create\fR(3C) and use the resulting signal to induce an
\fBEINTR\fR to polling threads.  (For code that need not be
portable, the \fBSIGEV_PORT\fR signal notification allows for explicit,
event-oriented timer notification to be sent to a specified port;
see \fBsignal.h\fR(3HEAD) for details.)
This facility therefore exists only to accommodate Linux-borne
applications and binaries; it is compatible with its Linux antecedent in both
binary interface and in semantics.

.SH SEE ALSO
.sp
.LP
\fBtimerfd_create\fR(3C), \fBtimerfd_gettime\fR(3C), \fBtimerfd_settime\fR(3C)