reltimer(3) Library Functions Manual reltimer(3)
NAME
reltimer - Establishes timeout intervals of a per-process timer
LIBRARY
Standard C Library (libc.a)
SYNOPSIS
#include <sys/timers.h>
int reltimer( timer_t tmrid, struct itimerspec *val, struct itimerspec *oval) ;
PARAMETERS
Specifies the per-process timer to access. Points to a type itimerspec structure containing the values of the initial and offset timeout
intervals. Points to a type itimerspec structure where the current value of the timer timeout interval and the time-to-go are to be
stored.
DESCRIPTION
The reltimer() function establishes initial and offset timeout intervals of a per-process timer specified by the tmrid parameter. Initial
and offset timeout interval information is stored in an itimerspec structure pointed to by the val parameter. When the per-process timer
specified by the tmrid parameter is active, after timeout of the initial time interval, all subsequent timeouts are controlled by the off-
set timeout value; as long as tmrid continues to operate, the offset values pointed to by the val parameter are used as the per-process
timeout interval. The current timeout interval and the time-to-go are returned to the location pointed to by the oval parameter.
Initial and offset time information for the per-process timer is stored in space reserved by a type itimerspec structure pointed to by the
val parameter. A type itimerspec structure is also used to store returned time information specified by the oval parameter. The itimerspec
structure is defined in the sys/timers.h include file.
NOTES
Time values smaller than the resolution of the specified timer are rounded up to the resolution value. Time values larger than the maximum
timeout value of the specified per-process timer are rounded down to that maximum value. Trial use
RETURN VALUES
Upon successful completion, the reltimer() function returns 0 (zero). Otherwise, -1 is returned and errno is set to indicate the error.
ERRORS
If the reltimer() function fails, errno may be set to the following value: The timerid parameter does not specify an allocated per-process
timer, or the val parameter points to a nanosecond value less than zero or greater than or equal to 1000 million.
RELATED INFORMATION
Functions: alarm(3), getclock(3), gettimer(3), mktimer(3) delim off
reltimer(3)
