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diff --git a/man3/ualarm.3 b/man3/ualarm.3 new file mode 100644 index 000000000..19e57b86f --- /dev/null +++ b/man3/ualarm.3 @@ -0,0 +1,111 @@ +.\" Copyright (c) 2003 Andries Brouwer (aeb@cwi.nl) +.\" +.\" 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, write to the Free +.\" Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, +.\" USA. +.\" +.TH UALARM 3 2003-07-24 "" "Linux Programmer's Manual" +.SH NAME +ualarm \- schedule signal after given number of microseconds +.SH SYNOPSIS +.nf +/* BSD version */ +.B "#include <unistd.h>" +.sp +.BI "unsigned int" +.br +.BI "ualarm(unsigned int " usecs ", unsigned int " interval ); +.sp +/* SUSv2 version */ +.B "#define _XOPEN_SOURCE 500" +.br +.B "#include <unistd.h>" +.sp +.BI "useconds_t ualarm(useconds_t " usecs ", useconds_t " interval ); +.fi +.SH DESCRIPTION +The \fBualarm()\fP function causes the signal 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, this signal will terminate the process. +.LP +If the +.I interval +argument is nonzero, further SIGALRM signals will be sent every +.I interval +microseconds after the first. +.SH "RETURN VALUE" +This function returns the number of microseconds remaining from +the previous call, or 0 when no alarm is pending. +.SH ERRORS +.TP +EINTR +Interrupted by a signal. +.TP +EINVAL +\fIusecs\fP or \fIinterval\fP is not smaller than 1000000. +(On systems where that is considered an error.) +.SH "CONFORMING TO" +BSD 4.3, POSIX 1003.1-2003. +BSD 4.3, SUSv2 and POSIX do not define any errors. +.SH NOTES +The type +.B useconds_t +is an unsigned integer type capable of holding integers +in the range [0,1000000]. +This type is defined by +.I <sys/types.h> +included by +.I <unistd.h> +but glibc defines it only when _XOPEN_SOURCE has a value not less than 500, +or both _XOPEN_SOURCE and _XOPEN_SOURCE_EXTENDED are defined. +.\" useconds_t also gives problems on HPUX 10. +Programs will be more portable if they never mention this type explicitly. +.LP +The interaction of this function with +other timer functions such as +.IR alarm (), +.IR sleep (), +.IR nanosleep (), +.IR setitimer (), +.IR timer_create (), +.IR timer_delete (), +.IR timer_getoverrun (), +.IR timer_gettime (), +.IR timer_settime (), +.IR usleep () +is unspecified. +.LP +This function is obsolete. Use +.BR nanosleep (2) +or +.BR setitimer (2) +instead. +.SH "SEE ALSO" +.BR alarm (2), +.BR getitimer (2), +.BR nanosleep (2), +.BR select (2), +.BR setitimer (2), +.BR usleep (3) |