wait.h File Reference

POSIX declarations for waiting (<sys/wait.h>) More...

#include <signal.h>
#include <sys/types.h>
#include <zephyr/kernel.h>

Include dependency graph for wait.h:

Go to the source code of this file.

Macros
#define	WCONTINUED   K_PROCESS_WCONTINUED
	Report status of any continued child process.
#define	WNOHANG   K_PROCESS_WNOHANG
	Do not hang if no status is available; return immediately.
#define	WUNTRACED   K_PROCESS_WUNTRACED
	Report status of stopped child process.
#define	WEXITSTATUS(wstatus)   K_WEXITSTATUS(wstatus)
	Exit status of a child that exited normally.
#define	WIFCONTINUED(wstatus)   ((wstatus) == 0xffff)
	True if the child has continued from a job control stop.
#define	WIFEXITED(wstatus)   K_WIFEXITED(wstatus)
	True if the child exited normally.
#define	WIFSIGNALED(wstatus)   K_WIFSIGNALED(wstatus)
	True if the child exited due to an uncaught signal.
#define	WIFSTOPPED(wstatus)   (((wstatus) & 0xff) == 0x7f)
	True if the child is currently stopped.
#define	WSTOPSIG(wstatus)   (((wstatus) >> 8) & 0xff)
	Signal number that caused the child to stop.
#define	WTERMSIG(wstatus)   K_WTERMSIG(wstatus)
	Signal number that caused the child to terminate.
#define	WEXITED   K_PROCESS_WEXITED
	Wait for processes that have exited.
#define	WNOWAIT   K_PROCESS_WNOWAIT
	Report the status of a selected process, leaving it waitable.
#define	WSTOPPED   K_PROCESS_WUNTRACED
	Wait for processes stopped by delivery of a signal.

Typedefs
typedef enum idtype	idtype_t
	Identifier kind selecting the scope of a waitid() operation.
typedef int	id_t
typedef int	pid_t

Enumerations
enum	idtype { P_ALL , P_PID , P_PGID }
	Identifier kind selecting the scope of a waitid() operation. More...

Functions
pid_t	wait (int *stat_loc)
	Wait for any child process to terminate.
int	waitid (idtype_t idtype, id_t id, siginfo_t *infop, int options)
	Wait for a child process matching idtype and id to change state.
pid_t	waitpid (pid_t pid, int *stat_loc, int options)
	Wait for a child process to terminate.

Detailed Description

POSIX declarations for waiting (<sys/wait.h>)

See also

POSIX.1-2017 <sys/wait.h>

Definition in file wait.h.

Macro Definition Documentation

WCONTINUED

#define WCONTINUED   K_PROCESS_WCONTINUED

Report status of any continued child process.

Definition at line 33 of file wait.h.

WEXITED

#define WEXITED   K_PROCESS_WEXITED

Wait for processes that have exited.

Definition at line 58 of file wait.h.

WEXITSTATUS

#define WEXITSTATUS

(

wstatus

)

K_WEXITSTATUS(wstatus)

Exit status of a child that exited normally.

Definition at line 41 of file wait.h.

WIFCONTINUED

#define WIFCONTINUED

(

wstatus

)

((wstatus) == 0xffff)

True if the child has continued from a job control stop.

Definition at line 44 of file wait.h.

WIFEXITED

#define WIFEXITED

(

wstatus

)

K_WIFEXITED(wstatus)

True if the child exited normally.

Definition at line 47 of file wait.h.

WIFSIGNALED

#define WIFSIGNALED

(

wstatus

)

K_WIFSIGNALED(wstatus)

True if the child exited due to an uncaught signal.

Definition at line 49 of file wait.h.

WIFSTOPPED

#define WIFSTOPPED

(

wstatus

)

(((wstatus) & 0xff) == 0x7f)

True if the child is currently stopped.

Definition at line 51 of file wait.h.

WNOHANG

#define WNOHANG   K_PROCESS_WNOHANG

Do not hang if no status is available; return immediately.

Definition at line 36 of file wait.h.

WNOWAIT

#define WNOWAIT   K_PROCESS_WNOWAIT

Report the status of a selected process, leaving it waitable.

Definition at line 60 of file wait.h.

WSTOPPED

#define WSTOPPED   K_PROCESS_WUNTRACED

Wait for processes stopped by delivery of a signal.

Definition at line 62 of file wait.h.

WSTOPSIG

#define WSTOPSIG

(

wstatus

)

(((wstatus) >> 8) & 0xff)

Signal number that caused the child to stop.

Definition at line 53 of file wait.h.

WTERMSIG

#define WTERMSIG

(

wstatus

)

K_WTERMSIG(wstatus)

Signal number that caused the child to terminate.

Definition at line 55 of file wait.h.

WUNTRACED

#define WUNTRACED   K_PROCESS_WUNTRACED

Report status of stopped child process.

Definition at line 38 of file wait.h.

Typedef Documentation

id_t

typedef int id_t

Definition at line 79 of file wait.h.

idtype_t

typedef enum idtype idtype_t

Identifier kind selecting the scope of a waitid() operation.

pid_t

typedef int pid_t

Definition at line 85 of file wait.h.

Enumeration Type Documentation

idtype

enum idtype

Identifier kind selecting the scope of a waitid() operation.

Enumerator
P_ALL	Wait for any child of the calling process.
P_PID	Wait for the child with a specific process ID.
P_PGID	Wait for any child in a specific process group.

Definition at line 66 of file wait.h.

Function Documentation

wait()

pid_t wait

(

int *

stat_loc

)

Wait for any child process to terminate.

Parameters

[out]

stat_loc

location in which to store the child's wait status; may be NULL.

Returns

the process ID of the reaped child on success, or -1 with errno set on failure.

See also

https://pubs.opengroup.org/onlinepubs/9699919799/functions/wait.html

waitid()

int waitid	(	idtype_t	idtype,
		id_t	id,
		siginfo_t *	infop,
		int	options
	)

Wait for a child process matching idtype and id to change state.

Parameters

	idtype	scope of the wait operation (P_ALL, P_PID, or P_PGID).
	id	process ID or process group ID, according to idtype.
[out]	infop	location in which to store the child's status information.
	options	bitwise OR of WEXITED, WNOHANG, and WNOWAIT.

Returns

0 on success, or -1 with errno set on failure.

See also

https://pubs.opengroup.org/onlinepubs/9699919799/functions/waitid.html

waitpid()

pid_t waitpid	(	pid_t	pid,
		int *	stat_loc,
		int	options
	)

Wait for a child process to terminate.

Parameters

	pid	child selection: a process ID, -1 for any child, 0 for the caller's process group, or a negated process group ID.
[out]	stat_loc	location in which to store the child's wait status; may be NULL.
	options	bitwise OR of WNOHANG and WUNTRACED.

Returns

the process ID of the child on success, or -1 with errno set on failure.

See also

https://pubs.opengroup.org/onlinepubs/9699919799/functions/waitpid.html