svcadm(1M)을 검색하려면 섹션에서 1M 을 선택하고, 맨 페이지 이름에 svcadm을 입력하고 검색을 누른다.
usleep(3)
USLEEP(3) Linux Programmer's Manual USLEEP(3)
NAME
usleep - suspend execution for microsecond intervals
SYNOPSIS
#include <unistd.h>
int usleep(useconds_t usec);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
usleep():
Since glibc 2.12:
(_XOPEN_SOURCE >= 500) && ! (_POSIX_C_SOURCE >= 200809L)
|| /* Glibc since 2.19: */ _DEFAULT_SOURCE
|| /* Glibc versions <= 2.19: */ _BSD_SOURCE
Before glibc 2.12:
_BSD_SOURCE || _XOPEN_SOURCE >= 500
DESCRIPTION
The usleep() function suspends execution of the calling thread for (at
least) usec microseconds. The sleep may be lengthened slightly by any
system activity or by the time spent processing the call or by the
granularity of system timers.
RETURN VALUE
The usleep() function returns 0 on success. On error, -1 is returned,
with errno set to indicate the cause of the error.
ERRORS
EINTR Interrupted by a signal; see signal(7).
EINVAL usec is greater than or equal to 1000000. (On systems where
that is considered an error.)
ATTRIBUTES
For an explanation of the terms used in this section, see
attributes(7).
allbox; lb lb lb l l l. Interface Attribute Value T{ usleep()
T} Thread safety MT-Safe
CONFORMING TO
4.3BSD, POSIX.1-2001. POSIX.1-2001 declares this function obsolete;
use nanosleep(2) instead. POSIX.1-2008 removes the specification of
usleep().
On the original BSD implementation, and in glibc before version 2.2.2,
the return type of this function is void. The POSIX version returns
int, and this is also the prototype used since glibc 2.2.2.
Only the EINVAL error return is documented by SUSv2 and POSIX.1-2001.
NOTES
The type useconds_t is an unsigned integer type capable of holding
integers in the range [0,1000000]. Programs will be more portable if
they never mention this type explicitly. Use
#include <unistd.h>
...
unsigned int usecs;
...
usleep(usecs);
The interaction of this function with the SIGALRM signal, and with
other timer functions such as alarm(2), sleep(3), nanosleep(2),
setitimer(2), timer_create(2), timer_delete(2), timer_getoverrun(2),
timer_gettime(2), timer_settime(2), ualarm(3) is unspecified.
SEE ALSO
alarm(2), getitimer(2), nanosleep(2), select(2), setitimer(2),
sleep(3), ualarm(3), time(7)
COLOPHON
This page is part of release 5.02 of the Linux man-pages project. A
description of the project, information about reporting bugs, and the
latest version of this page, can be found at
https://www.kernel.org/doc/man-pages/.
2017-09-15 USLEEP(3)