xref: /illumos-gate/usr/src/man/man7/timerfd.7 (revision dd72704bd9e794056c558153663c739e2012d721)
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14.Dd Feb 23, 2015
15.Dt TIMERFD 7
16.Os
17.Sh NAME
18.Nm timerfd
19.Nd Linux-compatible timer notification facility
20.Sh SYNOPSIS
21.In sys/timerfd.h
22.Sh DESCRIPTION
23.Nm
24is a Linux-borne facility for creating POSIX timers and
25receiving their subsequent events via a file descriptor.
26The facility itself is arguably unnecessary:
27portable code can either use the timeout value present in
28.Xr poll 2 /
29.Xr port_get 3C
30or -- if this is deemed of unacceptably poor resolution -- create a POSIX timer
31via
32.Xr timer_create 3C
33and use the resulting signal to induce an
34.Sy EINTR
35to polling threads.  (For code that need not be
36portable, the
37.Sy SIGEV_PORT
38signal notification allows for explicit, event-oriented timer notification to be
39sent to a specified port; see
40.Xr signal.h 3HEAD
41for details.) This facility therefore exists only to accommodate Linux-borne
42applications and binaries; it is compatible with its Linux antecedent in both
43binary interface and in semantics.
44.Sh SEE ALSO
45.Xr timerfd_create 3C ,
46.Xr timerfd_gettime 3C ,
47.Xr timerfd_settime 3C
48