sys_wait.h
Section: POSIX Programmer's Manual (0P)
Updated: 2017
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This manual page is part of the POSIX Programmer's Manual.
The Linux implementation of this interface may differ (consult
the corresponding Linux manual page for details of Linux behavior),
or the interface may not be implemented on Linux.
NAME
sys/wait.h
--- declarations for waiting
SYNOPSIS
#include <sys/wait.h>
DESCRIPTION
The
<sys/wait.h>
header shall define the following symbolic constants for use with
waitpid():
- WCONTINUED
-
Report status of continued child process.
- WNOHANG
-
Do not hang if no status is available; return immediately.
- WUNTRACED
-
Report status of stopped child process.
The
<sys/wait.h>
header shall define the following macros for analysis of process status
values:
- WEXITSTATUS
-
Return exit status.
- WIFCONTINUED
-
True if child has been continued.
- WIFEXITED
-
True if child exited normally.
- WIFSIGNALED
-
True if child exited due to uncaught signal.
- WIFSTOPPED
-
True if child is currently stopped.
- WSTOPSIG
-
Return signal number that caused process to stop.
- WTERMSIG
-
Return signal number that caused process to terminate.
The
<sys/wait.h>
header shall define the following symbolic constants as possible values
for the
options
argument to
waitid():
- WEXITED
-
Wait for processes that have exited.
- WNOWAIT
-
Keep the process whose status is returned in
infop
in a waitable state.
- WSTOPPED
-
Status is returned for any child that has stopped upon receipt of a
signal.
The
WCONTINUED
and WNOHANG constants, described above for
waitpid(),
can also be used with
waitid().
The type
idtype_t
shall be defined as an enumeration type whose possible values shall
include at least the following:
P_ALL
P_PGID
P_PID
The
<sys/wait.h>
header shall define the
id_t
and
pid_t
types as described in
<sys/types.h>.
The
<sys/wait.h>
header shall define the
siginfo_t
type and the
sigval
union as described in
<signal.h>.
Inclusion of the
<sys/wait.h>
header may also make visible
all symbols from
<signal.h>.
The following shall be declared as functions and may also be defined
as macros. Function prototypes shall be provided.
-
pid_t wait(int *);
int waitid(idtype_t, id_t, siginfo_t *, int);
pid_t waitpid(pid_t, int *, int);
The following sections are informative.
APPLICATION USAGE
None.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
<signal.h>,
<sys_resource.h>,
<sys_types.h>
The System Interfaces volume of POSIX.1-2017,
wait(),
waitid()
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1-2017, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 7, 2018 Edition,
Copyright (C) 2018 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group.
In the event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online at
http://www.opengroup.org/unix/online.html .
Any typographical or formatting errors that appear
in this page are most likely
to have been introduced during the conversion of the source files to
man page format. To report such errors, see
https://www.kernel.org/doc/man-pages/reporting_bugs.html .