nuttx/include/sys/times.h
Xiang Xiao af1dceb3e3 libc: Implement times function
https://pubs.opengroup.org/onlinepubs/009604599/functions/times.html

Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Change-Id: If2cccfedd532a77f86035d16d36d94ae38d8f09c
2021-07-21 13:11:54 -03:00

82 lines
2.9 KiB
C

/****************************************************************************
* include/sys/times.h
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
#ifndef __INCLUDE_SYS_TIMES_H
#define __INCLUDE_SYS_TIMES_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <sys/types.h>
/****************************************************************************
* Public Type Definitions
****************************************************************************/
/* Structure describing CPU time used by a process and its children. */
struct tms
{
clock_t tms_utime; /* User CPU time. */
clock_t tms_stime; /* System CPU time. */
clock_t tms_cutime; /* User CPU time of dead children. */
clock_t tms_cstime; /* System CPU time of dead children. */
};
#undef EXTERN
#if defined(__cplusplus)
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
/****************************************************************************
* Name: times
*
* Description:
* The times() function shall fill the tms structure pointed to by buffer
* with time-accounting information.
*
* Returned Value:
* Upon successful completion, times() shall return the elapsed real time,
* in clock ticks, since an arbitrary point in the past (for example,
* system start-up time). This point does not change from one invocation
* of times() within the process to another. The return value may overflow
* the possible range of type clock_t. If times() fails, (clock_t)-1 shall
* be returned and errno set to indicate the error.
*
****************************************************************************/
clock_t times(FAR struct tms *buffer);
#undef EXTERN
#if defined(__cplusplus)
}
#endif
#endif /* __INCLUDE_SYS_TIMES_H */