Amazon FreeRTOS: POSIX
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semaphore.h
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1 /*
2  * Amazon FreeRTOS POSIX V1.1.0
3  * Copyright (C) 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a copy of
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25 
33 #ifndef _FREERTOS_POSIX_SEMAPHORE_H_
34 #define _FREERTOS_POSIX_SEMAPHORE_H_
35 
36 /* FreeRTOS+POSIX includes. */
37 #include "FreeRTOS_POSIX/time.h"
38 #include "FreeRTOS_POSIX_types.h"
39 
43 typedef PosixSemType_t sem_t;
44 
54 int sem_destroy( sem_t * sem );
55 
65 int sem_getvalue( sem_t * sem,
66  int * sval );
67 
84 int sem_init( sem_t * sem,
85  int pshared,
86  unsigned value );
87 
95 int sem_post( sem_t * sem );
96 
114 int sem_timedwait( sem_t * sem,
115  const struct timespec * abstime );
116 
129 int sem_trywait( sem_t * sem );
130 
141 int sem_wait( sem_t * sem );
142 
143 #endif /* ifndef _FREERTOS_POSIX_SEMAPHORE_H_ */
sem_destroy
int sem_destroy(sem_t *sem)
Destroy an unnamed semaphore.
Definition: FreeRTOS_POSIX_semaphore.c:45
sem_timedwait
int sem_timedwait(sem_t *sem, const struct timespec *abstime)
Lock a semaphore with timeout.
Definition: FreeRTOS_POSIX_semaphore.c:129
time.h
Time types.
sem_wait
int sem_wait(sem_t *sem)
Lock a semaphore.
Definition: FreeRTOS_POSIX_semaphore.c:228
sem_init
int sem_init(sem_t *sem, int pshared, unsigned value)
Initialize an unnamed semaphore.
Definition: FreeRTOS_POSIX_semaphore.c:74
sem_getvalue
int sem_getvalue(sem_t *sem, int *sval)
Get the value of a semaphore.
Definition: FreeRTOS_POSIX_semaphore.c:57
sem_trywait
int sem_trywait(sem_t *sem)
Lock a semaphore if available.
Definition: FreeRTOS_POSIX_semaphore.c:206
timespec
represents an elapsed time
Definition: time.h:79
sem_t
PosixSemType_t sem_t
Semaphore type.
Definition: semaphore.h:43
sem_post
int sem_post(sem_t *sem)
Unlock a semaphore.
Definition: FreeRTOS_POSIX_semaphore.c:109