svcadm(8)을 검색하려면 섹션에서 8 을 선택하고, 맨 페이지 이름에 svcadm을 입력하고 검색을 누른다.
alarm(2)
alarm(2) System Calls alarm(2)
NAME
alarm - schedule an alarm signal
SYNOPSIS
#include <unistd.h>
unsigned int alarm(unsigned int seconds);
DESCRIPTION
The alarm() function causes the system to generate a SIGALRM signal for
the process after the number of real-time seconds specified by seconds
have elapsed (see signal.h(3HEAD)). Processor scheduling delays may
prevent the process from handling the signal as soon as it is gener‐
ated.
If seconds is 0, a pending alarm request, if any, is cancelled. If sec‐
onds is greater than LONG_MAX/hz, seconds is rounded down to
LONG_MAX/hz. The value of hz is normally 100.
Alarm requests are not stacked; only one SIGALRM generation can be
scheduled in this manner; if the SIGALRM signal has not yet been gener‐
ated, the call will result in rescheduling the time at which the
SIGALRM signal will be generated.
The fork(2) function clears pending alarms in the child process. A new
process image created by one of the exec(2) functions inherits the time
left to an alarm signal in the old process's image.
RETURN VALUES
If there is a previous alarm request with time remaining, alarm() re‐
turns a non-zero value that is the number of seconds until the previous
request would have generated a SIGALRM signal. Otherwise, alarm() re‐
turns 0.
ERRORS
The alarm() function is always successful; no return value is reserved
to indicate an error.
ATTRIBUTES
See attributes(7) for descriptions of the following attributes:
tab() box; cw(2.75i) |cw(2.75i) lw(2.75i) |lw(2.75i) ATTRIBUTE TYPEAT‐
TRIBUTE VALUE _ Interface StabilityCommitted _ MT-LevelAsync-Signal-
Safe _ StandardSee standards(7).
SEE ALSO
exec(2), fork(2), setitimer(2), timer_create(3C), signal.h(3HEAD), at‐
tributes(7), standards(7)
NOTES
The alarm() function is independent of the setitimer(2) and sleep(3C)
functions on Oracle Solaris, but this cannot be relied upon for some
other operating systems.
HISTORY
The alarm() function has been included in all Sun and Oracle releases
of Solaris.
Oracle Solaris 11.4 30 Jan 2023 alarm(2)