ждать, пока процесс изменит состояние, стиль BSD (wait for process to change state, BSD style)
Имя (Name)
wait3, wait4 - wait for process to change state, BSD style
Синопсис (Synopsis)
#include <sys/wait.h>
pid_t wait3(int *wstatus, int options, struct rusage *rusage);
pid_t wait4(pid_t pid, int *wstatus, int options,
struct rusage *rusage);
Feature Test Macro Requirements for glibc (see
feature_test_macros(7)):
wait3():
Since glibc 2.26:
_DEFAULT_SOURCE
|| (_XOPEN_SOURCE >= 500 &&
! (_POSIX_C_SOURCE >= 200112L
|| _XOPEN_SOURCE >= 600))
From glibc 2.19 to 2.25:
_DEFAULT_SOURCE || _XOPEN_SOURCE >= 500
Glibc 2.19 and earlier:
_BSD_SOURCE || _XOPEN_SOURCE >= 500
wait4():
Since glibc 2.19:
_DEFAULT_SOURCE
Glibc 2.19 and earlier:
_BSD_SOURCE
Описание (Description)
These functions are nonstandard; in new programs, the use of
waitpid(2) or waitid(2) is preferable.
The wait3() and wait4() system calls are similar to waitpid(2),
but additionally return resource usage information about the
child in the structure pointed to by rusage.
Other than the use of the rusage argument, the following wait3()
call:
wait3(wstatus, options, rusage);
is equivalent to:
waitpid(-1, wstatus, options);
Similarly, the following wait4() call:
wait4(pid, wstatus, options, rusage);
is equivalent to:
waitpid(pid, wstatus, options);
In other words, wait3() waits of any child, while wait4() can be
used to select a specific child, or children, on which to wait.
See wait(2) for further details.
If rusage is not NULL, the struct rusage to which it points will
be filled with accounting information about the child. See
getrusage(2) for details.
Возвращаемое значение (Return value)
As for waitpid(2).
Ошибки (Error)
As for waitpid(2).
Стандарты (Conforming to)
4.3BSD.
SUSv1 included a specification of wait3(); SUSv2 included
wait3(), but marked it LEGACY; SUSv3 removed it.
Примечание (Note)
Including <sys/time.h> is not required these days, but increases
portability. (Indeed, <sys/resource.h> defines the rusage
structure with fields of type struct timeval defined in
<sys/time.h>.)
C library/kernel differences
On Linux, wait3() is a library function implemented on top of the
wait4() system call.
Смотри также (See also)
fork(2), getrusage(2), sigaction(2), signal(2), wait(2),
signal(7)
