+++ /dev/null
-.\" Copyright (c) 2003 Andries Brouwer (aeb@cwi.nl)
-.\"
-.\" %%%LICENSE_START(GPLv2+_DOC_FULL)
-.\" This is free documentation; you can redistribute it and/or
-.\" modify it under the terms of the GNU General Public License as
-.\" published by the Free Software Foundation; either version 2 of
-.\" the License, or (at your option) any later version.
-.\"
-.\" The GNU General Public License's references to "object code"
-.\" and "executables" are to be interpreted as the output of any
-.\" document formatting or typesetting system, including
-.\" intermediate and printed output.
-.\"
-.\" This manual is distributed in the hope that it will be useful,
-.\" but WITHOUT ANY WARRANTY; without even the implied warranty of
-.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-.\" GNU General Public License for more details.
-.\"
-.\" You should have received a copy of the GNU General Public
-.\" License along with this manual; if not, see
-.\" <http://www.gnu.org/licenses/>.
-.\" %%%LICENSE_END
-.\"
-.TH UALARM 3 2013-12-23 "" "Linux Programmer's Manual"
-.SH NAME
-ualarm \- schedule signal after given number of microseconds
-.SH SYNOPSIS
-.nf
-.B "#include <unistd.h>"
-.sp
-.BI "useconds_t ualarm(useconds_t " usecs ", useconds_t " interval );
-.fi
-.sp
-.in -4n
-Feature Test Macro Requirements for glibc (see
-.BR feature_test_macros (7)):
-.in
-.sp
-.BR ualarm ():
-.ad l
-.RS 4
-.PD 0
-.TP 4
-Since glibc 2.12:
-.nf
-_BSD_SOURCE ||
- (_XOPEN_SOURCE\ >=\ 500 ||
- _XOPEN_SOURCE\ &&\ _XOPEN_SOURCE_EXTENDED) &&
- !(_POSIX_C_SOURCE\ >=\ 200809L || _XOPEN_SOURCE\ >=\ 700)
-.TP 4
-.fi
-Before glibc 2.12:
-_BSD_SOURCE || _XOPEN_SOURCE\ >=\ 500 ||
-_XOPEN_SOURCE\ &&\ _XOPEN_SOURCE_EXTENDED
-.PD
-.RE
-.ad b
-.SH DESCRIPTION
-The
-.BR ualarm ()
-function causes the signal
-.B SIGALRM
-to be sent to the invoking process after (not less than)
-.I usecs
-microseconds.
-The delay may be lengthened slightly by any system activity
-or by the time spent processing the call or by the
-granularity of system timers.
-.LP
-Unless caught or ignored, the
-.B SIGALRM
-signal will terminate the process.
-.LP
-If the
-.I interval
-argument is nonzero, further
-.B SIGALRM
-signals will be sent every
-.I interval
-microseconds after the first.
-.SH RETURN VALUE
-This function returns the number of microseconds remaining for
-any alarm that was previously set, or 0 if no alarm was pending.
-.SH ERRORS
-.TP
-.B EINTR
-Interrupted by a signal.
-.TP
-.B EINVAL
-\fIusecs\fP or \fIinterval\fP is not smaller than 1000000.
-(On systems where that is considered an error.)
-.SH ATTRIBUTES
-.SS Multithreading (see pthreads(7))
-The
-.BR ualarm ()
-function is thread-safe.
-.SH CONFORMING TO
-4.3BSD, POSIX.1-2001.
-POSIX.1-2001 marks
-.BR ualarm ()
-as obsolete.
-POSIX.1-2008 removes the specification of
-.BR ualarm ().
-4.3BSD, SUSv2, and POSIX do not define any errors.
-.SH NOTES
-POSIX.1-2001 does not specify what happens if the
-.I usecs
-argument is 0.
-.\" This case is not documented in HP-US, Solar, FreeBSD, NetBSD, or OpenBSD!
-On Linux (and probably most other systems),
-the effect is to cancel any pending alarm.
-
-The type
-.I useconds_t
-is an unsigned integer type capable of holding integers
-in the range [0,1000000].
-On the original BSD implementation, and in glibc before version 2.1,
-the arguments to
-.BR ualarm ()
-were instead typed as
-.IR "unsigned int" .
-Programs will be more portable if they never mention
-.I useconds_t
-explicitly.
-.LP
-The interaction of this function with
-other timer functions such as
-.BR alarm (2),
-.BR sleep (3),
-.BR nanosleep (2),
-.BR setitimer (2),
-.BR timer_create (2),
-.BR timer_delete (2),
-.BR timer_getoverrun (2),
-.BR timer_gettime (2),
-.BR timer_settime (2),
-.BR usleep (3)
-is unspecified.
-.LP
-This function is obsolete.
-Use
-.BR setitimer (2)
-or POSIX interval timers
-.RB ( timer_create (2),
-etc.)
-instead.
-.SH SEE ALSO
-.BR alarm (2),
-.BR getitimer (2),
-.BR nanosleep (2),
-.BR select (2),
-.BR setitimer (2),
-.BR usleep (3),
-.BR time (7)
-.SH COLOPHON
-This page is part of release 3.79 of the Linux
-.I man-pages
-project.
-A description of the project,
-information about reporting bugs,
-and the latest version of this page,
-can be found at
-\%http://www.kernel.org/doc/man\-pages/.
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