nanosleep(2) [freebsd man page]
NANOSLEEP(2) BSD System Calls Manual NANOSLEEP(2) NAME
nanosleep -- suspend process execution for an interval measured in nanoseconds LIBRARY
Standard C Library (libc, -lc) SYNOPSIS
#include <time.h> int nanosleep(const struct timespec *rqtp, struct timespec *rmtp); DESCRIPTION
The nanosleep() system call causes the calling thread to sleep until the time interval specified by rqtp has elapsed. An unmasked signal will cause it to terminate the sleep early, regardless of the SA_RESTART value on the interrupting signal. RETURN VALUES
If the nanosleep() system call returns because the requested time has elapsed, the value returned will be zero. If the nanosleep() system call returns due to the delivery of a signal, the value returned will be -1, and the global variable errno will be set to indicate the interruption. If rmtp is non-NULL, the timespec structure it references is updated to contain the unslept amount (the request time minus the time actually slept). ERRORS
The nanosleep() system call fails if: [EFAULT] Either rqtp or rmtp points to memory that is not a valid part of the process address space. [EINTR] The nanosleep() system call was interrupted by the delivery of a signal. [EINVAL] The rqtp argument specified a nanosecond value less than zero or greater than or equal to 1000 million. [ENOSYS] The nanosleep() system call is not supported by this implementation. SEE ALSO
sigsuspend(2), sleep(3) STANDARDS
The nanosleep() system call conforms to IEEE Std 1003.1b-1993 (``POSIX.1''). BSD
April 17, 1997 BSD
Check Out this Related Man Page
nanosleep(3) Library Functions Manual nanosleep(3) NAME
nanosleep - Suspends a process from execution for the specified timer interval (P1003.1b) LIBRARY
Realtime Library (librt.so, librt.a) SYNOPSIS
#include <time.h> int nanosleep ( const struct timespec *rqtp, struct timespec *rmtp); PARAMETERS
*rqtp A pointer to the timespec data structure that defines the time interval during which the calling process is suspended. *rmtp A pointer to the timespec data structure that receives the amount of time remaining in the previously requested interval, or zero if the full interval has elapsed. DESCRIPTION
The nanosleep function suspends a process until one of the following conditions is met: o The time interval specified in rqtp has elapsed. o A signal is delivered to the calling process and the action is to deliver a signal to a signal-catching function (or to terminate the process). The suspension time may be longer than requested because the argument value is rounded up to an integer multiple of the clock resolution, or due to the scheduling of other activity. Except when it is interrupted by a signal, the suspension time is not less than the time speci- fied by the rqtp argument (as measured by the system clock). RETURN VALUES
When the nanosleep function returns because the requested time has elapsed, the call is successful and a value of 0 (zero) is returned. If the nanosleep function returns because it was interrupted by a signal, a value of -1 is returned. If the rmtp argument is not NULL, the timespec structure referenced by the call is updated to contain the time remaining in the interval. If the rmtp argument is NULL, the remaining time is not returned. On an unsuccessful call, a value of -1 is returned and errno is set to indicate that an error occurred. ERRORS
The nanosleep function fails under the following conditions: [EINTR] The nanosleep function was interrupted by a signal. [EINVAL] The rqtp argument specified a nanosecond value less than zero or greater than or equal to 1000 million. RELATED INFORMATION
Functions: sleep(1) Guide to Realtime Programming delim off nanosleep(3)